Slavs were one of the dominant ethnic groups in Eastern and Southern Europe and were ruled by the Austro-Hungarian empire throughout much of the nineteenth century. The rising influence of nationalism in this time period led to the Slavic people campaigning for self-government. Ultimately, however, two competing schools of thought emerged: Austro-Slavism, which sought to have the Slavic people protected by the might of the Austro-Hungarian Empire, and Pan-Slavism, which sought an independent Slavic state under the protection of the Russian Empire.

The Hegelian Dialectic says that in every time period there is a competing thesis and antithesis, and that these two forces eventually merge to form a “synthesis.” This “synthesis” is then carried forward to the next time period and the process begins again. Karl Marx, in his Communist Manifesto, attempted to apply the Hegelian Dialectic to the struggle between the economic classes in the nineteenth century. For Marx, the competing thesis and antithesis were capitalism and communism.

Existentialism arose originally as an offshoot of the philosophical writings of Friedrich Nietzsche. Existentialism holds that the universe as a whole is meaningless, and that the responsibility rests with the individual for giving meaning to his or her life and the world around him or her. Existentialism was advocated for and popularized by figures such as Jean-Paul Sartre, Simone de Beauvoir, and Albert Camus in the mid-twentieth century. Sartre was among the most notable advocates of existentialism as a movement, in part because his works included both creative treatments of the philosophical tennets of the movement (in novels and plays) and academic explanations of these ideas.

The Hegelian Dialectic, developed by German philosopher Georg Wilhelm Friedrich Hegel, states that in every historical time period there is a prevailing thesis and an opposing antithesis that compete for control and that eventually merge to form a “synthesis.” According to Hegel, this “synthesis” is then carried forwards as the dominant “thesis”  (paradigm) of the next time period, where the process repeats itself. The Hegelian Dialectic has been massively influential in the fields of philosophy and cultural criticism.

In the years leading up to World War II, the militarization of Germany in conjunction with Hitler’s expansionist and racist rhetoric caused alarm throughout the nations of Europe. On the other hand, most governments were also heavily opposed to preemptively striking against Hitler and wanted to avoid war at all costs. The policy of appeasement conceded that it was better to give in to Hitler’s simpler demands if it preserved Europe's tenuous peace. The hands-off approach of appeasement led to the annexation of the Sudetenland (a German-speaking part of Czechoslovakia). Neville Chamberlain was the British Prime Minister at the time, and who was among the strongest advocates of the policy. Seeing that appeasement had failed as a policy, Chamberlain resigned his office shortly after the beginning of the war.

Nihilism is the belief that life is essentially meaningless, particularly that religion, morality, and spirituality are fundamentally meaningless. Nihilists believe that even if meaning were to exist, it would be impossible to communicate this meaning between humans. As a philosophical tradition, Nihilism dates back to the ancient Greeks (most notably Gorgias). Many influential philosophers, if not full Nihilists, were substantially influenced by nihilistic thinking, including Kierkegaard, Nietzsche, and Sartre, among many others.

Zionism first emerged in the late nineteenth century and picked up steam in the first few decades of the twentieth century. Zionists wanted a Jewish homeland, ideally located in Palestine. The Balfour Declaration, signed by the British government in 1917, promised to help provide a Jewish homeland in Palestine. This promise was eventually carried out after World War II, with the creation of Israel in 1948.

Fascism arose in the early nineteenth century and took power in Italy and Spain. Nazism is sometimes included under the umbrella of fascism and sometimes not; it depends on which historian you ask. The heart of the debate lies, basically, in the question of whether or not nazism is its own ideology, or a sub-category of fascism. In a fascist state, the rights of the workers are subjugated to the interests of nationalism and corporations. Fascism values nationalism and industry over any individual human rights.

Neocolonialism refers to the belief that colonialism never really came to an end. They argue that after World War II, and during the Cold War, the European powers stopped dominating nations with their military and instead dominated them economically through corporate and financial institutions and political pressure. Neocolonialism acknowledges the role of the military-industrial complex in the complicated nexus of financial and political measures used to exert pressure on weaker nations, but it sees the military itself as a small cog in the much larger, more complex machine of financial and political domination exerted by richer nations. 

The physiocrats were an eighteenth-century group who equated wealth with land and agriculture and who promoted a "hands-off" approach to government involvement in the economy. They were opponents of the mercantilists, who supported economic regulation by the government. In addition to coming much later in history, the Bolsheviks and National Socialists also supported government intervention in the economy.