The Neutrality of France

In 1914, Archduke Franz Ferdinand, heir to the Austrian-Hungarian throne, is assassinated in Sarajevo by a Serbian radical. Austria-Hungary decides to declare war on Serbia, which prompts Russia, a fellow Slavic state, to declare war upon Austria-Hungary

Germany, Austria-Hungary's ally, also declares war upon Serbia. Russia declares war on Germany, too. Because Germany declared war on Serbia and not upon Russia, France, a Russian ally, had no reason to declare war upon Germany. Therefore, France takes a neutral stance in the war.

Because of France's position, Germany only has one front to fight, allowing them to focus all of their attention on Russia. Germany and Austria-Hungary capture Moscow, forcing Russia to surrender. Due to family ties, Russia only has to cede large amounts of territory and make needed reforms such as abolishing serfdom.

Because of Germany and Austria Hungary's victory, the age of absolute monarchies lives on. World War II never occurs and the October Revolution never happens.