The violent event in 1914 helped start World War 1 was the assassination of Franz Ferdinand.
Most historians agree that the German invasion of Poland on September 1, 1939, was the event that marked the start of World War 2.
It outraged the Austro-Hungarians and caused world war I.
Most directly, the US entered World War II.
The Bolshevik Revolution was the event that led to Russia's early exit from World War 1. It was a costly war for Russia.
The violent event in 1914 helped start World War 1 was the assassination of Franz Ferdinand.
Most historians agree that the German invasion of Poland on September 1, 1939, was the event that marked the start of World War 2.
It was the assasination of archduke franz Ferdinand that directly started world war 1
The attack on Pearl harbour
The Germans invaded Poland early on the morning of September 1st, 1939. This was the start of World War II.
The Japanese bombing of Pearl Harbor.
France
the start of the Vietnam War
Start of the war, victory in Europe and victory over Japan.
What event marked the start of the French and Indian war
The War started when Adolf Hitler's Nazis Germany invaded Poland.
It outraged the Austro-Hungarians and caused world war I.