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.

During the Second World War, the three Axis powers of Germany, Italy, and Finland mobilized the largest share of their male population. For the Allies, the Soviet Union mobilized the largest share of men, as well as the largest total army of any country, but it was restricted in its ability to mobilize more due to the impact this would have on its economy. Other notable statistics come from the British Empire, where a larger share of men were drafted from Dominions than from the metropole, and there is also a discrepancy between the share of the black and white populations from South Africa.

However, it should be noted that there were many external factors from the war that influenced these figures. For example, gender ratios among the adult populations of many European countries was already skewed due to previous conflicts of the 20th century (namely WWI and the Russian Revolution), whereas the share of the male population eligible to fight in many Asian and African countries was lower than more demographically developed societies, as high child mortality rates meant that the average age of the population was much lower.

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.

Graph and download economic data for Population Level - Veterans, Vietnam-Era and Earlier Wartime Periods, 18 Years and over (LNU00077884) from Sep 2008 to Jun 2025 about korean war, Vietnam Era, World War, 18 years +, veterans, civilian, population, and USA.

United States - Population Level - Men, Veterans, World War II or Korean War or Vietnam Era, 18 Years and over was 4723.00000 Thous. of Persons in May of 2025, according to the United States Federal Reserve. Historically, United States - Population Level - Men, Veterans, World War II or Korean War or Vietnam Era, 18 Years and over reached a record high of 11434.00000 in September of 2008 and a record low of 4723.00000 in May of 2025. Trading Economics provides the current actual value, an historical data chart and related indicators for United States - Population Level - Men, Veterans, World War II or Korean War or Vietnam Era, 18 Years and over - last updated from the United States Federal Reserve on July of 2025.

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.

Graph and download economic data for Unemployment Rate - Veterans, Vietnam-Era and Earlier Wartime Periods, 18 Years and over (LNU04077884) from Sep 2008 to Jun 2025 about korean war, Vietnam Era, World War, 18 years +, veterans, household survey, unemployment, rate, and USA.

United States - Employment-Population Ratio - Veterans, World War II or Korean War or Vietnam Era, 18 Years and over was 11.80% in May of 2025, according to the United States Federal Reserve. Historically, United States - Employment-Population Ratio - Veterans, World War II or Korean War or Vietnam Era, 18 Years and over reached a record high of 38.20 in November of 2008 and a record low of 10.50 in April of 2025. Trading Economics provides the current actual value, an historical data chart and related indicators for United States - Employment-Population Ratio - Veterans, World War II or Korean War or Vietnam Era, 18 Years and over - last updated from the United States Federal Reserve on July of 2025.

As of 2021, there were over 200,000 living United States veterans who served in the Second World War. The Department of Veteran Affairs projects that the number of living veterans will decline rapidly in the fifteen years until 2036, at which point just a few hundred Americans who served in the war will be still alive. The passing of the "Greatest Generation" is seen as symbolic by some, as for many people they represented the era when the United States' power on the world stage was at its greatest. The Second World war is particularly remembered as a "just" war in the U.S., as the United States was seen as fighting for democracy and self-determination, and against the tyrannies of Fascism, Nazism, and Japanese Imperialism.

The United States' involvement in the Second World War

World War II marked the peak in military enlistments in U.S. history, with over 16 million service members serving worldwide during the conflict. The U.S. joined the war in 1941 due to Imperial Japan's attack on the U.S. naval base at Pearl Harbor, Hawaii, before joining the European theater of the war in 1944 during the Invasion of Normandy. The U.S. military played a vital role in the defeat of Nazi Germany on the Western Front in May 1945, while the Soviet Red Army defeated the Wehrmacht in the East. The U.S. was also vital in the defeat of Fascist Italy, as they had led an allied invasion force onto the Italian peninsula from Northern Africa in September 1943. The final action of the war took place in the Asian theater of war, as Imperial Japan was the last of the Axis powers to concede defeat to the Allies. The United States effectively ended the war with the dropping of two nuclear bombs on Hiroshima and Nagasaki in August 1945, leading to as many as a quarter of a million deaths. It remains to this day the sole use of atomic weapons in an active conflict.

This map layer shows the prevalent generations that make up the population of the United States using multiple scales. As of 2018, the most predominant generations in the U.S. are Baby Boomers (born 1946-1964), Millennials (born 1981-1998), and Generation Z (born 1999-2016). Currently, Millennials are the most predominant population in the U.S.A generation represents a group of people who are born around the same time and experience world events and trends during the same stage of life through similar mediums (for example, online, television, print, or radio). Because of this, people born in the same generation are expected to have been exposed to similar values and developmental experiences, which may cause them to exhibit similar traits or behaviors over their lifetimes. Generations provide scientists and government officials the opportunity to measure public attitudes on important issues by people’s current position in life and document those differences across demographic groups and geographic regions. Generational cohorts also give researchers the ability to understand how different developmental experiences, such as technological, political, economic, and social changes, influence people’s opinions and personalities. Studying people in generational groups is significant because an individual’s age is a conventional predictor for understanding cultural and political gaps within the U.S. population.Though there is no exact equation to determine generational cutoff points, it is understood that we designate generational spans based on a 15- to 20-year gap. The only generational period officially designated by the U.S. Census Bureau is based on the surge of births after World War II in 1946 and a significant decline in birth rates after 1964 (Baby Boomers). From that point, generational gaps have been determined by significant political, economic, and social changes that define one’s formative years (for example, Generation Z is considered to be marked by children who were directly affected by the al Qaeda attacks of September 11, 2001).In this map layer, we visualize six active generations in the U.S., each marked by significant changes in American history:The Greatest Generation (born 1901-1924): Tom Brokaw’s 1998 book, The Greatest Generation, coined the term ‘the Greatest Generation” to describe Americans who lived through the Great Depression and later fought in WWII. This generation had significant job and education opportunities as the war ended and the postwar economic booms impacted America.The Silent Generation (born 1925-1945): The title “Silent Generation” originated from a 1951 essay published in Time magazine that proposed the idea that people born during this period were more cautious than their parents. Conflict from the Cold War and the potential for nuclear war led to widespread levels of discomfort and uncertainty throughout the generation.Baby Boomers (born 1946-1964): Baby Boomers were named after a significant increase in births after World War II. During this 20-year span, life was dramatically different for those born at the beginning of the generation than those born at the tail end of the generation. The first 10 years of Baby Boomers (Baby Boomers I) grew up in an era defined by the civil rights movement and the Vietnam War, in which a lot of this generation either fought in or protested against the war. Baby Boomers I tended to have great economic opportunities and were optimistic about the future of America. In contrast, the last 10 years of Baby Boomers (Baby Boomers II) had fewer job opportunities and available housing than their Boomer I counterparts. The effects of the Vietnam War and the Watergate scandal led a lot of second-wave boomers to lose trust in the American government. Generation X (born 1965-1980): The label “Generation X” comes from Douglas Coupland’s 1991 book, Generation X: Tales for An Accelerated Culture. This generation was notoriously exposed to more hands-off parenting, out-of-home childcare, and higher rates of divorce than other generations. As a result, many Gen X parents today are concerned about avoiding broken homes with their own kids.Millennials (born 1981-1998): During the adolescence of Millennials, America underwent a technological revolution with the emergence of the internet. Because of this, Millennials are generally characterized by older generations to be technologically savvy.Generation Z (born 1999-2016): Generation Z or “Zoomers” represent a generation raised on the internet and social media. Gen Z makes up the most ethnically diverse and largest generation in American history. Like Millennials, Gen Z is recognized by older generations to be very familiar with and/or addicted to technology.Questions to ask when you look at this mapDo you notice any trends with the predominant generations located in big cities? Suburbs? Rural areas?Where do you see big clusters of the same generation living in the same area?Which areas do you see the most diversity in generations?Look on the map for where you, your parents, aunts, uncles, and grandparents live. Do they live in areas where their generation is the most predominant?

Throughout the 19th century, the share of military personnel employed by the United States government was below 0.2 percent of the total population in most years. There were noticeable spikes in enlistments and conscriptions during the American Civil War (1861-65), the First World War (1917-18*), and Second World War (1941-45*), as well as smaller increases during the Mexican-American War (1946-48) and the Spanish-American War (1898), but figures were generally much lower than the post-WWII era.

Following the Second World War, the United States abandoned many of its isolationist positions as it sought to become the world's leading superpower. This involved stationing millions of troops in overseas bases during the Cold War, in strategically important locations such as West Germany, Japan, and Taiwan. Additionally, involvement in conflicts such as the Korean War (1950-1953) and Vietnam War (1964-1973*) kept military employment high, usually between 1-2 percent until the 1970s. Figures remained just below the one percent mark until the 1990s, when the end of the Cold War and the growing influence of technology in conventional warfare saw a decrease in demand for many traditional combat roles. Despite U.S. involvement in a number of overseas conflicts in the 21st century, military personnel represented less than 0.5 percent of the total population in most years between 2000 and 2016.

This study focused on the effect of economic resources and racial/ethnic composition on the change in crime rates from 1970-2004 in United States cities in metropolitan areas that experienced a large growth in population after World War II. A total of 352 cities in the following United States metropolitan areas were selected for this study: Atlanta, Dallas, Denver, Houston, Las Vegas, Miami, Orange County, Orlando, Phoenix, Riverside, San Bernardino, San Diego, Silicon Valley (Santa Clara), and Tampa/St. Petersburg. Selection was based on the fact that these areas developed during a similar time period and followed comparable development trajectories. In particular, these 14 areas, known as the "boomburbs" for their dramatic, post-World War II population growth, all faced issues relating to the rapid growth of tract-style housing and the subsequent development of low density, urban sprawls. The study combined place-level data obtained from the United States Census with crime data from the Uniform Crime Reports for five categories of Type I crimes: aggravated assaults, robberies, murders, burglaries, and motor vehicle thefts. The dataset contains a total of 247 variables pertaining to crime, economic resources, and race/ethnic composition.

Estimates for the total death count of the Second World War generally range somewhere between 70 and 85 million people. The Soviet Union suffered the highest number of fatalities of any single nation, with estimates mostly falling between 22 and 27 million deaths. China then suffered the second greatest, at around 20 million, although these figures are less certain and often overlap with the Chinese Civil War. Over 80 percent of all deaths were of those from Allied countries, and the majority of these were civilians. In contrast, 15 to 20 percent were among the Axis powers, and the majority of these were military deaths, as shown in the death ratios of Germany and Japan. Civilian deaths and atrocities It is believed that 60 to 67 percent of all deaths were civilian fatalities, largely resulting from war-related famine or disease, and war crimes or atrocities. Systematic genocide, extermination campaigns, and forced labor, particularly by the Germans, Japanese, and Soviets, led to the deaths of millions. In this regard, Nazi activities alone resulted in 17 million deaths, including six million Jews in what is now known as The Holocaust. Not only was the scale of the conflict larger than any that had come before, but the nature of and reasoning behind this loss make the Second World War stand out as one of the most devastating and cruelest conflicts in history. Problems with these statistics Although the war is considered by many to be the defining event of the 20th century, exact figures for death tolls have proven impossible to determine, for a variety of reasons. Countries such as the U.S. have fairly consistent estimates due to preserved military records and comparatively few civilian casualties, although figures still vary by source. For most of Europe, records are less accurate. Border fluctuations and the upheaval of the interwar period mean that pre-war records were already poor or non-existent for many regions. The rapid and chaotic nature of the war then meant that deaths could not be accurately recorded at the time, and mass displacement or forced relocation resulted in the deaths of many civilians outside of their homeland, which makes country-specific figures more difficult to find. Early estimates of the war’s fatalities were also taken at face value and formed the basis of many historical works; these were often very inaccurate, but the validity of the source means that the figures continue to be cited today, despite contrary evidence.

In comparison to Europe, estimate ranges are often greater across Asia, where populations were larger but pre-war data was in short supply. Many of the Asian countries with high death tolls were European colonies, and the actions of authorities in the metropoles, such as the diversion of resources from Asia to Europe, led to millions of deaths through famine and disease. Additionally, over one million African soldiers were drafted into Europe’s armies during the war, yet individual statistics are unavailable for most of these colonies or successor states (notably Algeria and Libya). Thousands of Asian and African military deaths went unrecorded or are included with European or Japanese figures, and there are no reliable figures for deaths of millions from countries across North Africa or East Asia. Additionally, many concentration camp records were destroyed, and such records in Africa and Asia were even sparser than in Europe. While the Second World War is one of the most studied academic topics of the past century, it is unlikely that we will ever have a clear number for the lives lost in the conflict.

Although the founding fathers declared American independence in 1776, and the subsequent Revolutionary War ended in 1783, individual states did not officially join the union until 1787. The first states to ratify the U.S. Constitution were Delaware, Pennsylvania and New Jersey, in December 1787, and they were joined by the remainder of the thirteen ex-British colonies by 1790. Another three states joined before the turn of the nineteenth century, and there were 45 states by 1900. The final states, Alaska and Hawaii, were admitted to the union in 1959, almost 172 years after the first colonies became federal states. Secession in the American Civil War The issues of slavery and territorial expansion in the mid nineteenth century eventually led to the American Civil War, which lasted from 1861 until 1865. As the U.S. expanded westwards, a moral and economic argument developed about the legality of slavery in these new states; northern states were generally opposed to the expansion of slavery, whereas the southern states (who were economically dependent on slavery) saw this lack of extension as a stepping stone towards nationwide abolition. In 1861, eleven southern states seceded from the Union, and formed the Confederate States of America. When President Lincoln refused to relinquish federal property in the south, the Confederacy attacked, setting in motion the American Civil War. After four years, the Union emerged victorious, and the Confederate States of America was disbanded, and each individual state was readmitted to Congress gradually, between 1866 and 1870. Expansion of other territories Along with the fifty U.S. states, there is one federal district (Washington D.C., the capital city), and fourteen overseas territories, five of which with a resident population (American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the U.S. Virgin Islands). In 2019, President Trump inquired about the U.S. purchasing the territory of Greenland from Denmark, and, although Denmark's response indicated that this would be unlikely, this does suggest that the US may be open to further expansion of it's states and territories in the future. There is also a movement to make Washington D.C. the 51st state to be admitted to the union, as citizens of the nation's capital (over 700,000 people) do not have voting representation in the houses of Congress nor control over many local affairs; as of 2020, the U.S. public appears to be divided on the issue, and politicians are split along party lines, as D.C. votes overwhelmingly for the Democratic nominee in presidential elections.

In 1800, the region of Germany was not a single, unified nation, but a collection of decentralized, independent states, bound together as part of the Holy Roman Empire. This empire was dissolved, however, in 1806, during the Revolutionary and Napoleonic eras in Europe, and the German Confederation was established in 1815. Napoleonic reforms led to the abolition of serfdom, extension of voting rights to property-owners, and an overall increase in living standards. The population grew throughout the remainder of the century, as improvements in sanitation and medicine (namely, mandatory vaccination policies) saw child mortality rates fall in later decades. As Germany industrialized and the economy grew, so too did the argument for nationhood; calls for pan-Germanism (the unification of all German-speaking lands) grew more popular among the lower classes in the mid-1800s, especially following the revolutions of 1948-49. In contrast, industrialization and poor harvests also saw high unemployment in rural regions, which led to waves of mass migration, particularly to the U.S.. In 1886, the Austro-Prussian War united northern Germany under a new Confederation, while the remaining German states (excluding Austria and Switzerland) joined following the Franco-Prussian War in 1871; this established the German Empire, under the Prussian leadership of Emperor Wilhelm I and Chancellor Otto von Bismarck. 1871 to 1945 - Unification to the Second World War The first decades of unification saw Germany rise to become one of Europe's strongest and most advanced nations, and challenge other world powers on an international scale, establishing colonies in Africa and the Pacific. These endeavors were cut short, however, when the Austro-Hungarian heir apparent was assassinated in Sarajevo; Germany promised a "blank check" of support for Austria's retaliation, who subsequently declared war on Serbia and set the First World War in motion. Viewed as the strongest of the Central Powers, Germany mobilized over 11 million men throughout the war, and its army fought in all theaters. As the war progressed, both the military and civilian populations grew increasingly weakened due to malnutrition, as Germany's resources became stretched. By the war's end in 1918, Germany suffered over 2 million civilian and military deaths due to conflict, and several hundred thousand more during the accompanying influenza pandemic. Mass displacement and the restructuring of Europe's borders through the Treaty of Versailles saw the population drop by several million more.

Reparations and economic mismanagement also financially crippled Germany and led to bitter indignation among many Germans in the interwar period; something that was exploited by Adolf Hitler on his rise to power. Reckless printing of money caused hyperinflation in 1923, when the currency became so worthless that basic items were priced at trillions of Marks; the introduction of the Rentenmark then stabilized the economy before the Great Depression of 1929 sent it back into dramatic decline. When Hitler became Chancellor of Germany in 1933, the Nazi government disregarded the Treaty of Versailles' restrictions and Germany rose once more to become an emerging superpower. Hitler's desire for territorial expansion into eastern Europe and the creation of an ethnically-homogenous German empire then led to the invasion of Poland in 1939, which is considered the beginning of the Second World War in Europe. Again, almost every aspect of German life contributed to the war effort, and more than 13 million men were mobilized. After six years of war, and over seven million German deaths, the Axis powers were defeated and Germany was divided into four zones administered by France, the Soviet Union, the UK, and the U.S.. Mass displacement, shifting borders, and the relocation of peoples based on ethnicity also greatly affected the population during this time. 1945 to 2020 - Partition and Reunification In the late 1940s, cold war tensions led to two distinct states emerging in Germany; the Soviet-controlled east became the communist German Democratic Republic (DDR), and the three western zones merged to form the democratic Federal Republic of Germany. Additionally, Berlin was split in a similar fashion, although its location deep inside DDR territory created series of problems and opportunities for the those on either side. Life quickly changed depending on which side of the border one lived. Within a decade, rapid economic recovery saw West Germany become western Europe's strongest economy and a key international player. In the east, living standards were much lower, although unemployment was almost non-existent; internationally, East Germany was the strongest economy in the Eastern Bloc (after the USSR), though it eventually fell behind the West by the 1970s. The restriction of movement between the two states also led to labor shortages in t...

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.

In 1940, the Soviet Union produced significantly less industrial material than the United States in terms of natural resources and construction materials. The same was true when compared with Germany, apart from iron and steel; the USSR produced over double the amount of iron ore as Germany, and a similar amount of cast iron and steel. However, while the U.S. and Soviet populations were more comparable in 1940, Germany's population was around 70 million, which was 100 million fewer than the USSR; therefore the difference in per capita output was even higher in Germany than what is shown in the graph.

The Second World War severely altered the demographic composition of many countries, particularly in terms of gender ratios across certain age groups. For age groups below 14 years, there is little observable impact of the war on gender ratios, however, some countries see a drastic change across older generations, particularly in the Soviet Union. For men in their twenties (i.e. those in their late-teens or early-twenties when the war began), the ratio drops from 98 men per 100 women in the 15-19 age group, to 68 men per 100 women in the 25-29 group.

In addition to the Second World War, these figures are affected by trends in nature and other historical events. For example, women tend to have higher overall life expectancies than men, which typically sees gender ratios widen among older generations. The impact of the First World War is also most-observable in France's gender ratios for those aged in their fifties. Additionally, the gap in ratios remains high for the Soviet Union across older age groups due to the impact of the First World War and the famine of the early 1930s, however the figures for Russia itself are even lower as it was disproportionately affected by the Russian Revolution and famine of the 1920s.

In 1800, the population of Japan was just over 30 million, a figure which would grow by just two million in the first half of the 19th century. However, with the fall of the Tokugawa shogunate and the restoration of the emperor in the Meiji Restoration of 1868, Japan would begin transforming from an isolated feudal island, to a modernized empire built on Western models. The Meiji period would see a rapid rise in the population of Japan, as industrialization and advancements in healthcare lead to a significant reduction in child mortality rates, while the creation overseas colonies would lead to a strong economic boom. However, this growth would slow beginning in 1937, as Japan entered a prolonged war with the Republic of China, which later grew into a major theater of the Second World War. The war was eventually brought to Japan's home front, with the escalation of Allied air raids on Japanese urban centers from 1944 onwards (Tokyo was the most-bombed city of the Second World War). By the war's end in 1945 and the subsequent occupation of the island by the Allied military, Japan had suffered over two and a half million military fatalities, and over one million civilian deaths.

The population figures of Japan were quick to recover, as the post-war “economic miracle” would see an unprecedented expansion of the Japanese economy, and would lead to the country becoming one of the first fully industrialized nations in East Asia. As living standards rose, the population of Japan would increase from 77 million in 1945, to over 127 million by the end of the century. However, growth would begin to slow in the late 1980s, as birth rates and migration rates fell, and Japan eventually grew to have one of the oldest populations in the world. The population would peak in 2008 at just over 128 million, but has consistently fallen each year since then, as the fertility rate of the country remains below replacement level (despite government initiatives to counter this) and the country's immigrant population remains relatively stable. The population of Japan is expected to continue its decline in the coming years, and in 2020, it is estimated that approximately 126 million people inhabit the island country.

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.