Answer:
The First World War, which lasted from 1914 to 1918, was a global conflict that involved many of the world's great powers, organized into two opposing military alliances: the Allies (primarily made up of France, Russia, and the United Kingdom) and the Central Powers (primarily made up of Germany, Austria-Hungary, and the Ottoman Empire). The war was characterized by the use of modern weapons and tactics, such as machine guns, artillery, and poison gas, which resulted in unprecedented levels of destruction and loss of life.
The war was precipitated by a number of factors, including militarism, imperialism, and nationalism, which had been building for decades leading up to the conflict. In addition, there were specific incidents and events that contributed to the outbreak of war, such as the assassination of Archduke Franz Ferdinand of Austria-Hungary in 1914, which was used as a pretext for Austria-Hungary to declare war on Serbia.
One of the main reasons why the First World War is considered the determining event of the twentieth century is because it had far-reaching consequences that shaped the course of history in the decades that followed. The war led to the collapse of several empires, including the Ottoman Empire and the Austro-Hungarian Empire, and contributed to the rise of new powers, such as the United States and the Soviet Union. The war also had a significant impact on the international order, leading to the creation of the League of Nations, which was the precursor to the United Nations.
In addition to its political and social consequences, the First World War also had a profound economic impact, as it disrupted global trade and led to widespread inflation and economic instability. The war also had a profound cultural impact, as it led to the creation of new art movements, such as Dadaism and Surrealism, and had a lasting impact on literature, music, and other forms of artistic expression.
Overall, the First World War was a major turning point in world history, and its consequences continue to be felt today.
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