4th August 1914 was when war was declared.
The war began in 1914, but not every country joined in at the same time, and some countries dropped out before the war ended in 1918.
Serbia
It began in 1914 and ended in 1918 i think
1914
1914
November 1, 1955
Germany
After
It didn't begin in 2039.
September 1, 1939. The first day of the war.
quagmire
1914 WWII 1939