What was a cause of World War I? the unification of separate German states into one nation

Austria-Hungary’s imperialist ambitions to dominate the Balkans

the invasion of Belgium by German troops

Russia’s desire to stay out of military alliances

Austria-Hungary’s imperialist ambitions to dominate the Balkans

Explanation:

The World War I was a period of battle between various countries from 1914 to 1918. It started formally on the 28th of July, 1914 and ended on the 11th of November, 1918.

One of the cause of World War I was Austria-Hungary’s imperialist ambitions to dominate the Balkans. Austria-Hungary was a dual monarchy that was established with the Austro-Hungarian Compromise of 1867 and it had so much power in Central Europe. Austria took charge of Bosnia and Herzegovina so as to avail it the opportunity to gain power in the Balkans, as against the Russian empire gaining authority and power. This led to the Great Balkan Crisis and by extension the World War I when other nations joined in alliance with their counterparts.

During World War I, some countries such as Germany, Great Britain (British empire), Canada, Austria-Hungary, used chemical weapons (poisonous gases) e.g chlorine gas. Also, various countries formed two alliances (Allied powers and Central powers) during the World War I, the Central powers included nations such as Germany, the Ottoman empire, and Austria-Hungary while the Allied powers included nations such as France, Great Britain (British empire) and the Russian empire.

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