What single event set in motion the start of WW1?
http://en.wikipedia.org/wiki/Assassination_of_Archduke_Franz_Ferdinand_of_Austria
The single event that set in motion the start of World War I was the assassination of Archduke Franz Ferdinand of Austria on June 28, 1914. To understand how this event led to the start of WW1, let's break it down into a few steps:
1. The assassination: Archduke Franz Ferdinand, the heir to the Austro-Hungarian throne, was assassinated in Sarajevo, Bosnia, by a young Serbian nationalist named Gavrilo Princip. This event alone did not immediately ignite the war, but it triggered a chain of events that led to an escalating conflict.
2. Austrian ultimatum to Serbia: Austria-Hungary blamed Serbia for the assassination and issued an ultimatum on July 23, 1914. The ultimatum presented a series of demands to Serbia, seeking their compliance within 48 hours. The demands were intentionally designed to provoke a refusal, leading to military action.
3. Serbian response and mobilization: Serbia responded partially accepting the ultimatum but rejecting some of the demands. As tensions escalated, Serbia began mobilizing its army.
4. Declarations of war: Austria-Hungary, unsatisfied with Serbia's response, declared war on Serbia on July 28, 1914. This triggered a series of alliances and treaties between different nations, which soon spiraled into a full-scale war. Russia, Serbia's ally, began mobilizing its forces to support Serbia, which led to Germany declaring war on Russia to defend Austria-Hungary. The domino effect continued as various nations joined the conflict based on their alliances, and World War I unfolded.
So, the assassination of Archduke Franz Ferdinand directly led to Austria-Hungary's ultimatum to Serbia, the Serbian response, and the subsequent declarations of war. However, it is important to note that the underlying causes of the war, such as longstanding rivalries, territorial disputes, and intricate web of alliances, were already in place, and the assassination simply acted as a catalyst, pushing the nations closer to an all-out war.