The US finally entered World War I in 1917, when it had bogged down after three years of fighting. The additional manpower turned the tide, and by 1919 Germany had lost most of its territorial gains. The war was ended by the Treaty of Versailles on June 28, 1919.
1917
1917 smart
1941
1917.
April 1917
As soon as the US entered the war in December 1941
1909 to 1944 The US entered World War 2 in December of 1941.
The US entered the war on April 6,1917
The US entered World War 1 on April 6, 1917. It remained in the war until it ended about a year and a half later.
The US entered World War 1 on April 6, 1917. The war ended about one and a half years later.
The US entered in 1941, after the Pearl Harbor bombing. I'm guessing this is where you are from?
1918
Fdr