Answer:
Archduke Franz Ferdinand was assassinated in June of 1914. After much hand-wringing and indecision on the proper response, <u><em>Austria-Hungary</em></u> declared war on Serbia in August of 1914. Europe was entangled in a series of complicated alliances that involved both Serbia and Austria. Serbia was allied with <u><em>Russia</em></u>, which was allied with <u><em>France</em></u>. While <u><em>Britain</em></u> was in agreement with, but not yet in a formal alliance with France, Austria and its ally <u><em>Germany</em></u> formed the Central Powers, and by the end of August 1914 all these nations were at war.
Explanation:
World War I was the first conflict to involve all the world, and because of that, everything related to alliances was completely new. For the most part, the first year of the war was so complicated that even the generals and leaders didn't understand it. Each country formed its alliances based on proximity, trade, culture or something that was correlated or to achieve a certain goal such as territory or goods.
