How did assassination of archduke franz ferdinand lead to start of world war?

 The assassination of Archduke Franz Ferdinand of Austria-Hungary on June 28, 1914, is widely recognized as the immediate spark that ignited World War I. Here is a step-by-step explanation:

1. **Archduke Franz Ferdinand's Role:** Franz Ferdinand was the heir to the Austro-Hungarian throne, and his assassination carried significant political ramifications.

2. **The Assassination:** The archduke and his wife, Sophie, were killed in Sarajevo by Gavrilo Princip, a Bosnian Serb nationalist associated with a group called Young Bosnia, which had ties to the Serbian nationalist organization known as the Black Hand.

3. **Austro-Hungarian Ultimatum:** Austria-Hungary, with the backing of Germany (its ally), saw the assassination as a direct threat to its authority and issued an ultimatum to Serbia with severe demands that Serbia would find almost impossible to accept fully.

4. **Serbia's Response:** While Serbia agreed to most of the demands, it only partially complied with some and outright refused others. This partial compliance did not satisfy Austria-Hungary.

5. **Austria-Hungary Declares War:** On July 28, 1914, Austria-Hungary declared war on Serbia, several weeks after the assassination of the archduke.

6. **Activation of Alliances:** This declaration of war triggered a complex web of alliances that had been formed over the previous decades. Russia had an agreement to protect Serbia, Germany was allied with Austria-Hungary, and France had an alliance with Russia.

7. **Germany's Military Strategy:** Germany executed a military strategy known as the Schlieffen Plan, which involved invading France through Belgium (a neutral country at the time) to quickly knock France out of the war before turning east to fight Russia.

8. **Worldwide Involvement:** Belgium's neutrality was guaranteed by Britain, which then declared war on Germany on August 4, 1914, leading to a global conflict as colonies and alliances brought more countries into the war.

Ultimately, the assassination was a catalyst that let loose the underlying tensions and rivalries in Europe, which had been growing due to imperialism, militarism, nationalism, and the entangled alliances.