Question

why first world war happened

Answer 1

there are somany reasons of first world war but the main reasons are: aggressive nationalism, imperialism, militarism, Balkan politics, secret alliances and immediate cause.....
hope this helps you...

Answer 2

Although there were a number of causes for the war, the assassination of Austrian Archduke Franz Ferdinand was the main catalyst for starting thewar. After the assassination, Austria declared war on Serbia. Then Russia prepared to defend its ally Serbia. Next, Germany declared war on Russia to protect Austria.
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