From 1273 until 1918, Austria was the seat of power of the House of Habsburg; one of Europe's most powerful and influential royal families of the past millennium. During this time and in the subsequent century since the Austro-Hungarian Empire's dissolution, the borders and demography of the Austrian state have changed dramatically, with the population growing from approximately three million people in 1800 to just over nine million in 2020. The area of modern Austria's population rose gradually throughout the nineteenth century, until the early 1900s, where it then dropped and fluctuated during the World Wars, before rising again until recent years.

End of an empire

The assassination of the heir to the Austrian throne, Archduke Franz Ferdinand, in Sarajevo on June 28, 1914, caused Austria to declare war on Serbia, which marked the outbreak of the First World War. The war (and subsequent Spanish Flu pandemic) would see the deaths of more than 1.2 million people from the Austro-Hungarian Empire, and the area of modern Austria's population dropped by almost 400,000 people between 1916 and 1920. In the years preceding the First World War, Slavic nationalism and tensions between various ethnicities in the empire had escalated to a new level; following the dissolution of Austria-Hungary in 1918, new states such as Poland, Czechoslovakia and Yugoslavia were created for corresponding ethnic groups, while Austrian and Hungarian states were created for ethnic Germans and Magyars respectively (Austria still uses this border today). The Treaty of Versailles had forbidden Austria from joining Germany, however in 1938, German Chancellor Adolf Hitler (who was born in Austria) united the two nations as part of the German Third Reich, with overwhelming support by the people of Austria. In the next few years, Austria's population decreased slightly, as a result of the forced relocation of Jews and the outbreak of the Second World War. Due to the Austria-German union, separate records were not kept for Austrian and German deaths during the war, however most estimates put Austria's total at over 350,000 fatalities.

Post-war Austria

Following Germany's defeat, Austria was split into four separately administered sections, and then the Second Austrian Republic was established in 1955, declaring its permanent neutrality in foreign affairs. In the period after this Austria has enjoyed a period of continued prosperity with a high standard of living and reasonable economic growth. Population growth stagnated in the 80's with the legalization of abortion and improved access to contraception, but has grown steadily in the past three decades. Austria is consistently ranked among the top 20 richest countries in the world in terms of GDP per capita, and in 2018 it was ranked 20th in the world by the Human Development Index.

Austria: Cisleithania was the Austrian-ruled section of the Austro-Hungarian Empire. This graphic shows the total population of Austria: Cisleithania from 1818 until 1910, just before the outbreak of World War I. As we can see from the graph, the population grows rather gradually throughout this 92 year period. The only dip in population comes between 1846 and 1851, possibly as a result of the revolutions that took place in 1848. After this time the population continues to grow before reaching over 28.5 million people in 1910.

The later stages of the Austro-Hungarian Empire's history were marked by a period of internal tensions between the varying ethnic groups, as the ethnic Slavs, Czechs and Romance groups felt oppressed by the ruling Germanic and Magyar peoples. The Empire was then dissolved in 1918 following its defeat during the First World War, and a number of new states were formed in the aftermath.

Bosnia and Herzegovina's total population grew at quite a steady rate from the early nineteenth century until the mid-1900s, increasing from 852,000 people in 1818 to 2.7 million in 1950. Following the Second World War, the population grew at an even faster rate, reaching 4.5 million people by the end of the 1980s. Throughout this period, Bosnia and Herzegovina was never an independent country, as it belonged to the Ottoman Empire until 1875, before it was then annexed by Austria-Hungary until the First World War, after which it became a part of Yugoslavia. During this time, ethnic Bosnians (the majority of which were Muslim) often faced oppression and persecution, and even mass genocide during the Second World War (when it was briefly annexed by Croatia, which was a puppet state of Nazi Germany). The Bosnian War From 1989 onwards, Bosnia's population decreased drastically, by approximately 750,000 people by the end of the century. This sudden change coincides with the dissolution of Yugoslavia, where the country experienced economic instability in the 1980s and then the independence of its internal states in the early 90s; Bosnia and Herzegovina itself became independent in 1992. The formation of an independent state lead to civil unrest among the different ethnic groups within Bosnia and Herzegovina, resulting in the Bosnian War that caused the deaths of approximately 100 thousand people, as well as the displacement of over 2.2 million. Modern Bosnia and Herzegovina Since this period in Bosnia and Herzegovina's history the population has never recovered, and a further decline in the past decade has seen the population fall below 3.3 million people in 2020; which is a decrease of more than one million people since the war. As the country seemingly comes to terms with its difficult past, and deals with high unemployment and ethnic tensions; there are some indicators for a brighter outlook for Bosnia and Herzegovina's future. Today, Bosnia and Herzegovina is seen as a developing country and economy, it is an applicant for both EU and NATO membership, and an emerging tourism sector may provide much-needed employment across the country.

Since the beginning of the 20th century, the total number of independent nation states in Europe has almost doubled, from 24 countries in 1900 to 45 today. At the beginning of this period, much of Central and Eastern Europe was split between the empires of Austria-Hungary, Germany, the Ottomans, and Russia. The dissolution of these empires in the aftermath of the First World War resulted in the restoration or creation of several independent states, such as Czechoslovakia, Poland, and Yugoslavia. During the interwar period, there were generally 33 countries in Europe, before the Second World War saw Germany and the Soviet Union annex most of the territories between them, and control of these regions swapped between the two during the remainder of the war. Germany also invaded several Western European countries, and there were fewer than 20 independent countries in Europe at the peak of the war. Post-war Europe The post-war period then saw some major restructuring of Europe's borders, and most of the defeated Axis governments fell under Allied influence. However, there was then a split between the leading Allied Powers, and the continent was divided between the east and west. The communist, eastern countries, known as the Eastern Bloc, mostly fell under the influence of the Soviet Union; whereas the West remained largely democratic and was under American influence (but to a lesser extent). Both sides of Europe prospered throughout the post-war period, but the Eastern Bloc economies eventually collapsed or stagnated, and independence movements gained more momentum. Communist regimes across Europe began collapsing in 1989, before the Soviet Union's dissolution in late 1991. Soviet dissolution resulted in the formation of 15 separate countries, seven of which were in Europe, while Yugoslavia's eventually resulted in seven new states. Post-communist separation While the borders of Western Europe remained fairly stable throughout the entire period, Eastern Europe's changed greatly. A large part of this can be attributed to cultural and historical differences between different ethnic groups in the region, who were often forced to share their lands under various empires or world powers; the fall of communism provided an opportunity for these groups to separate, but it was not always a peaceful process. This was most notable in the Yugoslav Wars in the 1990s, where some states achieved independence through violence, while others descended into it thereafter. Communism's collapse also resulted in the expansion of European integration, and many eastern countries joined the European Union in the early-2000s; this resulted in a mass exodus of economic migrants from the former-Eastern Bloc, which has had a significant demographic and economic impact on both sides of the continent. Generally, political relations across the east have improved greatly in recent years, and prosperity is growing. However, there has been a noticeable rise in authoritarian leadership across Eastern Europe, and Russian interference in foreign politics is growing; it remains to be seen what impact this will have on the stability of the region.