In Soviet Russia (RSFSR) in 1939 and 1959, ethnic Russians made up the largest share of the total population, with a share of approximately 83 percent. Tatars were the second largest ethnic group, followed by Ukrainians. Russians were consistently the largest ethnic group in the Soviet Union as a whole, with an overall share of 53 percent in 1979.

The Second World War had a profound impact on gender ratios within the Soviet Union's population, and its effect on different age groups varied greatly. The Soviet population structure had already been shaped heavily by the First World War, the Russian Revolution, and the famines of the early 1920s and early 1930s. The impact of these events on mortality and fertility meant that, in 1941, the generations whose births corresponded with these events had a lower population than would be expected on a typical population model. For example, in 1941, those aged between 5 and 9 had a significantly lower population than those aged 10 to 14, due to the effects of the Soviet famine of 1932-1933. Additionally, women outnumbered men in all age groups except the very youngest, due to the disproportionate effect of conflict and infant mortality on male populations. Impact of WWII In order to observe the impact of the war, one must compare populations of specific age groups in 1941 with the following age group in 1946. For men of "fighting age" in 1941, i.e. those aged between 15 and 44, these populations experience the most substantial decrease over the course of the war. For example, there are 5.6 million men aged 15-19 in 1941, but just 3.5 million aged 20-24 in 1946, giving a decrease of 38 percent. This decrease of almost forty percent can be observed until the 45-49 group, where the difference is 25 percent. Additionally, women aged between 15 and 34 saw a disproportionate decrease in their populations over this period, as many enlisted in the army and took an active part in the conflict, most notably as medics, snipers, and pilots.

The war's impact on fertility and child mortality meant that, in 1946, the total population under four years old was less than half its size in 1941. Generally, variations between age groups then fluctuated in line with pre-war patterns, however the overall ratio of women to men increased further after the war. For all age groups over 20 years, the number of men decreased between these years, whereas all women's age groups over 30 years saw an increase; this meant that, despite the war, women over 30 had a higher life expectancy in 1946.

In 1938, the year before the outbreak of the Second world War, the countries with the largest populations were China, the Soviet Union, and the United States, although the United Kingdom had the largest overall population when it's colonies, dominions, and metropole are combined. Alongside France, these were the five Allied "Great Powers" that emerged victorious from the Second World War. The Axis Powers in the war were led by Germany and Japan in their respective theaters, and their smaller populations were decisive factors in their defeat. Manpower as a resource In the context of the Second World War, a country or territory's population played a vital role in its ability to wage war on such a large scale. Not only were armies able to call upon their people to fight in the war and replenish their forces, but war economies were also dependent on their workforce being able to meet the agricultural, manufacturing, and logistical demands of the war. For the Axis powers, invasions and the annexation of territories were often motivated by the fact that it granted access to valuable resources that would further their own war effort - millions of people living in occupied territories were then forced to gather these resources, or forcibly transported to work in manufacturing in other Axis territories. Similarly, colonial powers were able to use resources taken from their territories to supply their armies, however this often had devastating consequences for the regions from which food was redirected, contributing to numerous food shortages and famines across Africa, Asia, and Europe. Men from annexed or colonized territories were also used in the armies of the war's Great Powers, and in the Axis armies especially. This meant that soldiers often fought alongside their former-enemies. Aftermath The Second World War was the costliest in human history, resulting in the deaths of between 70 and 85 million people. Due to the turmoil and destruction of the war, accurate records for death tolls generally do not exist, therefore pre-war populations (in combination with other statistics), are used to estimate death tolls. The Soviet Union is believed to have lost the largest amount of people during the war, suffering approximately 24 million fatalities by 1945, followed by China at around 20 million people. The Soviet death toll is equal to approximately 14 percent of its pre-war population - the countries with the highest relative death tolls in the war are found in Eastern Europe, due to the intensity of the conflict and the systematic genocide committed in the region during the war.

The population of Europe was estimated to be 745 million in 2024, an increase of around 4 million when compared with 2012. Over 35 years between 1950 and 1985, the population of Europe grew by approximately 157.8 million. But 35 years after 1985 it was estimated to have only increased by around 38.7 million. Since the 1960s, population growth in Europe has fallen quite significantly and was even negative during the mid-1990s. While population growth has increased slightly since the low of -0.07 percent in 1998, the growth rate for 2020 was just 0.04 percent. Which European country has the biggest population? As of 2024, the population of Russia was estimated to be approximately 144.8 million and was by far Europe's largest country in terms of population, with Turkey being the second-largest at over 87 million. While these two countries both have territory in Europe, however, they are both only partially in Europe, with the majority of their landmasses being in Asia. In terms of countries wholly located on the European continent, Germany had the highest population at 84.5 million, and was followed by the United Kingdom and France at 69.1 million and 66.5 million respectively. Characteristics of Europe's population There are approximately 384.6 million females in Europe, compared with 359.5 million males, a difference of around 25 million. In 1950, however, the male population has grown faster than the female one, with the male population growing by 104.7 million, and the female one by 93.6 million. As of 2024, the single year of age with the highest population was 37, at 10.6 million, while in the same year there were estimated to be around 136 thousand people aged 100 or over.

This graph shows the total population of Estonia, Latvia and Lithuania in the years between 1922 and 1935, as well as the total number of males and females. After the First World War the Baltic states began claiming their independence from tsarist Russia, as the events of the Russian Revolution took place. Inter-war Estonia The Estonian War of Independence from 1918 to 1920 led to the country's first period of independence, until it became occupied by the Soviet Union again in 1940 during the Second World War. After Estonia gained independence the country experienced a period of political turmoil, including a failed coup d'etat in 1924, and was hit hard by the Great Depression in 1929 before things became more stable in the mid 1930s. Between 1939 and 1945 Estonia's population was devastated by the Second World War, with some estimates claiming that as many as 7.3 percent of all civilians perished as a result of the conflict. From the graph we can see the population grew by 119 thousand people during the 12 years shown, growing from 1.107 million to 1.126 million. The number of women was also higher than the number of men during this time, by 67 thousand in 1922 and 68 thousand in 1934. Inter-war Latvia For Latvia, Independence was a hard-won struggle that had devastated the population in the late 1910s. Similarly to Estonia, the advent of independence brought many challenges to Latvia, and a period of political and economic turmoil followed, which was exacerbated by the Great Depression in 1929. After economic recovery began in 1933, and a coup d'etat established stricter control in 1934, the Latvian economy and political landscape became more stable and the quality of life improved. This lasted until the Second World War, where Latvia became one of the staging grounds of Germany's war against Soviet Russia, and approximately 12.5 percent of all civilians died. From the data we can see that Latvia's population between 1925 and 1935 grew steadily by 95,000 in this decade, with the number of men and women growing at a similar rate. Inter-war Lithuania Lithuania's experience in the interwar period was slightly different to that of Latvia and Estonia. The end of the First World War led to a growing movement for independence from German, Russian or Polish influence, however these countries were reluctant to cede control to one another, and independence was finally achieved in 1922. A right wing dictatorship was established in 1926, which maintained political and civil control until the outbreak of the Second World War, however interference from other nations, particularly Germany, was ever-present in Lithuanian economic activity. From the graph we have only one set of figures, showing that the Lithuanian population was just over 2 million in 1929, with approximately 5 percent more women than men. World War II again devastated Lithuania's population, with almost 14.4 percent of the entire population falling during the conflict.

The fertility rate of a country is the average number of children that women from that country will have throughout their reproductive years. From 1840 until 1910, Russia's fertility rate was relatively consistent, remaining between 6.7 and 7.4 children per woman during this time. Between 1910 and 1920, the fertility rate drops sharply as a result of the First World War and Russian Revolution (for individual years of WWI, the fertility rate dropped as low as 3.4). From 1920 to 1930 the fertility rate returns above 6 again, however a gradual decline then begins, and by the end of the Second World War, the Russian segment of the Soviet Union's fertility rate was below 2. The population experienced a relatively small 'baby boom' in the two decades following the war, but then the fertility rate dropped again, most sharply between 1990 and 1995 at the end of the Soviet Union's reign. Russia's fertility rate reached its lowest point in 2000 when it fell to just 1.25 children per woman, but in the past two decades it has risen again, and is expected to reach 1.8 in 2020.

Over the course of the Second World War approximately 127.2 million people were mobilized. The world's population in 1940 was roughly 2.3 billion, meaning that between five and six percent of the world was drafted into the military in some capacity. Approximately one in every 25 people mobilized were women, who generally served in an administrative or medical role, although hundreds of thousands of women did see active combat. Largest armies In absolute numbers, the Soviet Union mobilized the largest number of people at just under 34.5 million, and this included roughly 35 percent of the USSR's male population. By the war's end, more Soviets were mobilized than all European Axis powers combined. However, in relative terms, it was Germany who mobilized the largest share of its male population, with approximately 42 percent of men serving. The USSR was forced to find a balance between reinforcing its frontlines and maintaining agricultural and military production to supply its army (in addition to those in annexed territory after 1941), whereas a large share of soldiers taken from the German workforce were replaced by workers drafted or forcibly taken from other countries (including concentration camp prisoners and PoWs). Studying the figures The figures given in these statistics are a very simplified and rounded overview - in reality, there were many nuances in the number of people who were effectively mobilized for each country, their roles, and their status as auxiliary, collaborative, or resistance forces. The British Empire is the only power where distinctions are made between the metropole and its colonies or territories, whereas breakdowns of those who fought in other parts of Asia or Africa remains unclear. Additionally, when comparing this data with total fatalities, it is important to account for the civilian death toll, i.e. those who were not mobilized.

Throughout the 19th century, what we know today as Poland was not a united, independent country; apart from a brief period during the Napoleonic Wars, Polish land was split between the Austro-Hungarian, Prussian (later German) and Russian empires. During the 1800s, the population of Poland grew steadily, from approximately nine million people in 1800 to almost 25 million in 1900; throughout this time, the Polish people and their culture were oppressed by their respective rulers, and cultural suppression intensified following a number of uprisings in the various territories. Following the outbreak of the First World War, it is estimated that almost 3.4 million men from Poland served in the Austro-Hungarian, German and Russian armies, with a further 300,000 drafted for forced labor by the German authorities. Several hundred thousand were forcibly resettled in the region during the course of the war, as Poland was one of the most active areas of the conflict. For these reasons, among others, it is difficult to assess the extent of Poland's military and civilian fatalities during the war, with most reliable estimates somewhere between 640,000 and 1.1 million deaths. In the context of present-day Poland, it is estimated that the population fell by two million people in the 1910s, although some of this was also due to the Spanish Flu pandemic that followed in the wake of the war.

Poland 1918-1945

After more than a century of foreign rule, an independent Polish state was established by the Allied Powers in 1918, although it's borders were considerably different to today's, and were extended by a number of additional conflicts. The most significant of these border conflicts was the Polish-Soviet War in 1919-1920, which saw well over 100,000 deaths, and victory helped Poland to emerge as the Soviet Union's largest political and military rival in Eastern Europe during the inter-war period. Economically, Poland struggled to compete with Europe's other powers during this time, due to its lack of industrialization and infrastructure, and the global Great Depression of the 1930s exacerbated this further. Political corruption and instability was also rife in these two decades, and Poland's leadership failed to prepare the nation for the Second World War. Poland had prioritized its eastern defenses, and some had assumed that Germany's Nazi regime would see Poland as an ally due to their shared rivalry with the Soviet Union, but this was not the case. Germany invaded Poland on September 1, 1939, in the first act of the War, and the Soviet Union launched a counter invasion on September 17; Germany and the Soviet Union had secretly agreed to do this with the Molotov-Ribbentrop Pact in August, and had succeeded in taking the country by September's end. When Germany launched its invasion of the Soviet Union in 1941 it took complete control of Poland, which continued to be the staging ground for much of the fighting between these nations. It has proven difficult to calculate the total number of Polish fatalities during the war, for a variety of reasons, however most historians have come to believe that the figure is around six million fatalities, which equated to almost one fifth of the entire pre-war population; the total population dropped by four million throughout the 1940s. The majority of these deaths took place during the Holocaust, which saw the Nazi regime commit an ethnic genocide of up to three million Polish Jews, and as many as 2.8 million non-Jewish Poles; these figures do not include the large number of victims from other countries who died after being forcefully relocated to concentration camps in Poland.

Post-war Poland

The immediate aftermath of the war was also extremely unorganized and chaotic, as millions were forcefully relocated from or to the region, in an attempt to create an ethnically homogenized state, and thousands were executed during this process. A communist government was quickly established by the Soviet Union, and socialist social and economic policies were gradually implemented over the next decade, as well as the rebuilding, modernization and education of the country. In the next few decades, particularly in the 1980s, the Catholic Church, student groups and trade unions (as part of the Solidarity movement) gradually began to challenge the government, weakening the communist party's control over the nation (although it did impose martial law and imprison political opponent throughout the early-1980s). Increasing civil unrest and the weakening of Soviet influence saw communism in Poland come to an end in the elections of 1989. Throughout the 1990s, Poland's population growth stagnated at around 38.5 million people, before gradually decreasing since the turn of the millennium, to 37.8 million people in 2020. This decline was mostly due to a negative migration rate, as Polish workers could now travel more freely to Western Europea...

It is estimated that the Second World War was responsible for the deaths of approximately 3.76 percent of the world's population between 1939 and 1945. In 2022, where the world's population reached eight billion, this would be equal to the death of around 300 million people.

The region that experienced the largest loss of life relative to its population was the South Seas Mandate - these were former-German territories given to the Empire of Japan through the Treaty of Versailles following WWI, and they make up much of the present-day countries of the Marshall Islands, Micronesia, the Northern Mariana Islands (U.S. territory), and Palau. Due to the location and strategic importance of these islands, they were used by the Japanese as launching pads for their attacks on Pearl Harbor and in the South Pacific, while they were also taken as part of the Allies' island-hopping strategy in their counteroffensive against Japan. This came at a heavy cost for the local populations, a large share of whom were Japanese settlers who had moved there in the 1920s and 1930s. Exact figures for both pre-war populations and wartime losses fluctuate by source, however civilian losses in these islands were extremely high as the Japanese defenses resorted to more extreme measures in the war's final phase.

Over the course of the long nineteenth century, Estonia's population almost tripled, from 0.33 million in 1800, to over one million at the outbreak of the First World War. Throughout this time, Estonia was a part of the Russian Empire, however Germany then annexed the region during the First World War; when the German army eventually retreated in 1918, Estonian forces prevented Russia from re-taking the area in the Estonian War of Independence, and an independent Estonian Republic was gradually established between 1918 and 1920. Relative to its size and population, Estonia developed into a prosperous and peaceful nation in the interwar period, and Estonian language and culture thrived, although political stability proved difficult for the Baltic state.

Estonia in WWII Estonia's independence was short lived, as the country was then annexed by the Soviet Union as part of the secret Molotov-Ribbentrop Pact between Germany and the Soviets. The invasion was achieved with little-to-no conflict, as Estonia capitulated when faced with the vastly superior military and navy of the Soviet Union. Annexation became official in June 1940; a puppet, communist government was quickly established, and many military and political rivals were imprisoned or executed under Soviet control. When Germany invaded the Soviet Union the following year, they quickly took control of Estonia, but simply replaced the Soviet Union's rule with their own, and did not grant re-establish sovereignty as many Estonians had expected or hoped for. By the war's end, Estonia suffered approximately 83,000 deaths at the hands of the Soviet Union and Germany, with almost 50,000 of these civilian deaths, and the rest were fatalities of Estonian soldiers who were forced to fight in other nations' armies.

Post-war Estonia Following the war, Estonia remained under Soviet control, and between 1950 and 1990, the population of Estonia grew steadily, from 1.1 million to almost 1.6 million. In the wake of the Soviet Union's collapse, Estonia established a rapid, but peaceful independence in 1991; and the population dropped by roughly ten percent by the end of the century. This was mostly due to non-Estonians returning to their country or region of origin, although a wave of Estonian emigration soon followed. Estonia joined the European Union in 2004, and from 2000 until 2015, Estonia's population continued to fall, reaching just 1.3 million people in 2015. Recent years, however, have seen a reversal in this trend, with limited growth since 2015; although demographers predict that Estonia's population will drop below one million people in the next half-century. The past three decades have marked the longest continuous period in the past 800 years, where the region of Estonia was not under German, Polish, Russian or Scandinavian control.

The Second World War had a sever impact on gender ratios across European countries, particularly in the Soviet Union. While the United States had a balanced gender ratio of one man for every woman, in the Soviet Union the ratio was below 5:4 in favor of women, and in Soviet Russia this figure was closer to 4:3.

As young men were disproportionately killed during the war, this had long-term implications for demographic development, where the generation who would have typically started families in the 1940s was severely depleted in many countries.

During the eighteenth century, it is estimated that France's population grew by roughly fifty percent, from 19.7 million in 1700, to 29 million by 1800. In France itself, the 1700s are remembered for the end of King Louis XIV's reign in 1715, the Age of Enlightenment, and the French Revolution. During this century, the scientific and ideological advances made in France and across Europe challenged the leadership structures of the time, and questioned the relationship between monarchial, religious and political institutions and their subjects. France was arguably the most powerful nation in the world in these early years, with the second largest population in Europe (after Russia); however, this century was defined by a number of costly, large-scale conflicts across Europe and in the new North American theater, which saw the loss of most overseas territories (particularly in North America) and almost bankrupted the French crown. A combination of regressive taxation, food shortages and enlightenment ideologies ultimately culminated in the French Revolution in 1789, which brought an end to the Ancien Régime, and set in motion a period of self-actualization.

War and peace

After a volatile and tumultuous decade, in which tens of thousands were executed by the state (most infamously: guillotined), relative stability was restored within France as Napoleon Bonaparte seized power in 1799, and the policies of the revolution became enforced. Beyond France's borders, the country was involved in a series of large scale wars for two almost decades, and the First French Empire eventually covered half of Europe by 1812. In 1815, Napoleon was defeated outright, the empire was dissolved, and the monarchy was restored to France; nonetheless, a large number of revolutionary and Napoleonic reforms remained in effect afterwards, and the ideas had a long-term impact across the globe. France experienced a century of comparative peace in the aftermath of the Napoleonic Wars; there were some notable uprisings and conflicts, and the monarchy was abolished yet again, but nothing on the scale of what had preceded or what was to follow. A new overseas colonial empire was also established in the late 1800s, particularly across Africa and Southeast Asia. Through most of the eighteenth and nineteenth century, France had the second largest population in Europe (after Russia), however political instability and the economic prioritization of Paris meant that the entire country did not urbanize or industrialize at the same rate as the other European powers. Because of this, Germany and Britain entered the twentieth century with larger populations, and other regions, such as Austria or Belgium, had overtaken France in terms of industrialization; the German annexation of Alsace-Lorraine in the Franco-Prussian War was also a major contributor to this.

World Wars and contemporary France

Coming into the 1900s, France had a population of approximately forty million people (officially 38 million* due to to territorial changes), and there was relatively little growth in the first half of the century. France was comparatively unprepared for a large scale war, however it became one of the most active theaters of the First World War when Germany invaded via Belgium in 1914, with the ability to mobilize over eight million men. By the war's end in 1918, France had lost almost 1.4 million in the conflict, and approximately 300,000 in the Spanish Flu pandemic that followed. Germany invaded France again during the Second World War, and occupied the country from 1940, until the Allied counter-invasion liberated the country during the summer of 1944. France lost around 600,000 people in the course of the war, over half of which were civilians. Following the war's end, the country experienced a baby boom, and the population grew by approximately twenty million people in the next fifty years (compared to just one million in the previous fifty years). Since the 1950s, France's economy quickly grew to be one of the strongest in the world, despite losing the vast majority of its overseas colonial empire by the 1970s. A wave of migration, especially from these former colonies, has greatly contributed to the growth and diversity of France's population today, which stands at over 65 million people in 2020.

In 1750, when Finland was part of the Duchy of Sweden, and had a total population of just 422 thousand. Over the next 55 years the population grows steadily and reaches 896 thousand people, before it drops to 863 thousand in 1810. The Finnish borders did expand during the early 1800s, adding 12,000 people in 1809 and 185 thousand in 1811, however the dip in the graph most probably occurs as a result of the Finnish War, fought between Sweden and Russia in 1808 and 1809, and this war resulted in Finland becoming a part of the Russian Empire. From 1810 to 1865 the population then grows steadily again, until 1870 when it dips again from 1.84 million to 1.77 million. This second dip in population size is due to the Finnish famine of 1866-68, which resulted in the fatalities of around 8.5% of the entire Finnish population.

Throughout the twentieth century and until now the population has grown with each entry in the graph. Finland gained independence in 1918 after a brief civil war, and it was also heavily involved in fighting against Russia in World War II, and between 85 and 90 thousand people (2.3 to 2.6 percent of the total population) are estimated to have died as a direct result of the war. In spite of this the population has grown at a consistent rate (although the graph appears skewed as the intervals change from 10 years to 5 years in 1950), and the total population is expected to reach 5.5 million in 2020

In 1800, the population of the area of modern-day Lithuania was estimated to be just under 780,000. Lithuania’s rate of population growth would remain largely unchanged in the 19th century, as the Russian Empire would slowly but gradually develop its border regions. While large numbers of Lithuanians would emigrate west-ward (largely to the United States) between 1867 and 1868 after a famine in the country, growth would remain largely uninterrupted until the beginning of the First World War in 1912, which would see Lithuania, like much of the Baltic region, devastated as the battleground between the German and Russian Empires. As the conflict spread, those who were not made to evacuate by orders from the Russian government would face economic turmoil under German occupation, and as a result, Lithuania’s population would fall from just under 2.9 million in 1910, to under 2.3 million by 1920.

While Lithuania’s population would start to grow once more following the end of the First World War, this growth would be short-lived, as economic turmoil from the Great Depression, and later occupation and campaigns of mass extermination in the Second World War, most notably the extermination of 95 to 97 percent of the country’s Jewish population in the Holocaust, would cause Lithuania’s population growth to stagnate throughout the 1930s and 1940s. In the years following the end of the Second World War, Lithuania’s population would steadily climb, as industrialization by the Soviet Union would lead to improved economic growth and access to health, and campaigns of mass immunization and vaccination would lead to a sharp decline in child mortality. As a result, by the 1990s, Lithuania would have a population of over 3.7 million. However, Lithuania’s population would rapidly decline in the years following the dissolution of the Soviet Union in 1991, as economic crises and mass emigration from the country, paired with sharp declines in fertility, would result in a dramatic reduction in population. As a result, in 2020, Lithuania is estimated to have a population of just over 2.7 million.

In 1844, Romania had a population of just 3.6 million people. During the early entries in this data, Romania's borders were very different and much smaller than today, and control of this area often switched hands between the Austrian, Ottoman and Russian empires. The populations during this time are based on estimates made for incomplete census data, and they show that the population grows from 3.6 million in 1844, doubling to 7.2 million in 1912, part of this growth is due to a high natural birth rate during this period, but also partly due to the changing of Romania's borders and annexation of new lands. During this time Romania gained its independence from the Ottoman Empire as a result of the Russo-Turkish War in 1878, and experienced a period of increased stability and progress.

Between 1912 and 1930 the population of Romania grew by over 10 million people. The main reason for this is the huge territories gained by Romania in the aftermath of the First World War. During the war Romania remained neutral for the first two years, after which it joined the allies; however, it was very quickly defeated and overrun by the Central Powers, and in total it lost over 600 thousand people as a direct result of the war. With the collapse of the Austro-Hungarian and Russian empires after the war, Romania gained almost double it's territory, which caused the population to soar to 18.1 million in 1930. The population then decreases by 1941 and again by 1948, as Romania seceded territory to neighboring countries and lost approximately half a million people during the Second World War. From 1948 onwards the population begins to grow again, reaching it's peak at 23.5 million people in 1990.

Like many other Eastern European countries, there was very limited freedom of movement from Romania during the Cold War, and communist rule was difficult for the Romanian people. The Romanian Revolution in 1989 ended communist rule in the country, Romania transitioned to a free-market society and movement from the country was allowed. Since then the population has fallen each year as more and more Romanians move abroad in search of work and opportunities. The population is expected to fall to 19.2 million in 2020, which is over 4 million fewer people than it had in 1990.

The world's Jewish population has had a complex and tumultuous history over the past millennia, regularly dealing with persecution, pogroms, and even genocide. The legacy of expulsion and persecution of Jews, including bans on land ownership, meant that Jewish communities disproportionately lived in urban areas, working as artisans or traders, and often lived in their own settlements separate to the rest of the urban population. This separation contributed to the impression that events such as pandemics, famines, or economic shocks did not affect Jews as much as other populations, and such factors came to form the basis of the mistrust and stereotypes of wealth (characterized as greed) that have made up anti-Semitic rhetoric for centuries. Development since the Middle Ages The concentration of Jewish populations across the world has shifted across different centuries. In the Middle Ages, the largest Jewish populations were found in Palestine and the wider Levant region, with other sizeable populations in present-day France, Italy, and Spain. Later, however, the Jewish disapora became increasingly concentrated in Eastern Europe after waves of pogroms in the west saw Jewish communities move eastward. Poland in particular was often considered a refuge for Jews from the late-Middle Ages until the 18th century, when it was then partitioned between Austria, Prussia, and Russia, and persecution increased. Push factors such as major pogroms in the Russian Empire in the 19th century and growing oppression in the west during the interwar period then saw many Jews migrate to the United States in search of opportunity.

For most of the Second World War, the Soviet Union had the largest number of active military personnel each year, peaking at over 12 million people in the war's final years. The Soviet Union's ability to draw from its larger population was decisive in its eventual victory over Germany in 1945, whose eastern forces were greatly diminished by 1944 after it had already suffered heavy losses fighting the Soviets and was then forced to fight on the western front.

Each of the Great Powers had varying conscription systems in place that allowed them to draft citizens into the military. In the U.S., over 50 million men aged 18-45 would register for the draft before the war's end, and over 10 million of these were inducted into the military (alongside volunteers and those already in service). Conscription in Japan grew more aggressive as the war progressed, and its armed forces doubled in size in the final two years of the war.

When the Winter War broke out between Finland and the Soviet Union in late 1939, international attention turned to the Nordic countries. The neutral country of Norway in particular held strategic importance for Germany, not only due to its naval access to the Atlantic, but also as it was the most efficient route for the transport of Swedish iron to Germany. Norway had the fourth largest shipping fleet in the world, and both sides knew that control of Norway would significantly impact the German war effort; Britain and France had planned a preemptive invasion of Norway in early 1940, however Germany acted faster. Invasion On April 9, 1940, Operation Weserübung was launched, which was the simultaneous invasion of Denmark and Norway. Norway was very unprepared for the surprise attack, and Germany's prioritization of Norwegian air and naval bases hindered the response further. The rapidity of the invasion saw Denmark capitulate within a few hours, and Germany quickly took control of several Norwegian cities with little difficulty. It took several days for the Norwegian military to regroup and coordinate a response. With the help of an Allied expeditionary force and the British Navy, it achieved some success in the North Sea, but the delay had allowed enough time for German armored reinforcements to arrive and secure control of south and central Norway. By early May, most of the fighting had been pushed north, especially around Narvik; the main port for Swedish iron exports to Germany. Narvik was actually re-taken by the Allies on May 28, before they withdrew from Norway 10 days later to support the defense of France. Norway's king and government then left for London, where they formed a government-in-exile, and the final Norwegian military units surrendered on June 10 (after much of their resources were sent to Britain). Despite it taking just two months, the German invasion of Norway was the longest of any in Western Europe. Occupation Germany had planned on allowing the Norwegian government to remain in power (as in Denmark), to legitimize the occupation, but it quickly became clear that this would not be the case. Administrative councils were created, and a puppet government eventually installed, but ultimate control lay with the SS. The occupying force of more than 340,000 German troops was one of the largest per capita forces of the war, and, with hindsight, German investment in Norway's defense far outweighed its eventual use. The Norwegian underground resistance was very active throughout the war, both on land and at sea, and was responsible for some of the most effective sabotage missions carried out against Germany. The Norwegian economy, which had been dependent on international trade, was redirected towards the German war effort and it then shrunk massively. For Norway's citizens, restrictions were less strict than in other territories, but thousands of perceived opponents were still imprisoned or executed, and acts of terror were common. Around two thirds of Norway's Jewish population fled (mostly to Sweden) or went into hiding. However 773 were arrested and deported to concentration camps in Eastern Europe; the majority of these prisoners eventually perished in Auschwitz, and just 38 returned after the war. Liberation As the Soviets pushed the Germans back through Scandinavia in late 1944, German forces adopted a scorched-earth policy as they moved through the northern region of Finnmark. Thousands of homes were burned, and as many as 25,000 Norwegians were forced to live in the wilderness throughout the winter. In November 1944, exiled Norwegian troops and police officers arrived in Russia to take back Finnmark and rescue its citizens; the area was secured by the time of Germany's surrender on May 8, 1945. At the time of surrender, the resistance helped coordinate an effective and generally peaceful transfer of power, before the king and government's return on June 7. Immediately after the war, there were over 140,000 displaced foreigners in Norway, over half of which were Soviet prisoners of war, and over 90,000 displaced Norwegians abroad, mostly in Sweden. Norwegian authorities also investigated 92,000 cases of collaboration, which resulted in 46,000 convictions, 18,000 imprisonments, and 25 executions of Norwegian citizens. Estimates of total Norwegian deaths due to the war are generally around 10,000, although a precise breakdown for the fatalities remains unclear.