July 28, 1914, Austria-Hungary declare war on Serbia. The game of alliances took place, Russia declared war on Austria-Hungary followed by Prussia. France therefore declared war on Prussia anxious to keep the balance in the German Confederation. But the United Kingdom, with which tensions had persisted since 1870, declared war on France to restore balance in Europe.
In the first weeks of the war, Hanover and its allies merged with the Prussian armies to hold the Franco-Austro-Hungarian Front. Russia moved to Galicia-Lodomeria. In the colonies scattered battles are formed in Sub-Saharan Africa. In the colonies the situation changed very quickly in 1915 when the Ottoman Empire declared war on Egypt then under the wing of France. It was also the same year that Bulgaria went to war against Serbia while Greece declared war on Albania then under the Austro-Italian proctectorate.
In early 1916, Romania joined Russia to open a front in Transylvania. Austria-Hungary is then routed even if it resists thanks to Italian aid. But on May 26, 1916, off the coast of Bordeaux, a transatlantic ship transporting Americans was sunk by mistake by the United Kingdom, which led to the entry into the war of the United States. The pressure in Europe drops a little, the United Kingdom having to defend Canada.
The year 1917 marked the start of the explosion of Austria-Hungary, which, beaten on all fronts, saw the ethnic tensions of the empire resurface. At the end of the year, victory seems leaning for the Triple Alliance of Russia, Prussia and the United Kingdom, Austria-Hungary is in the grip of a Hungarian communist revolution, its allies lose their colonies one by one but of on the other side of the Atlantic, Canada is hopelessly defended.
It was in 1918 that France and Italy, alone against all, saw their front collapse. The United States preferring a separate peace will capitulate France followed by Italy having lost all hope of victory."