Harry s. Truman
The US President was Woodrow Wilson.
US President Truman said that the war was over 13 December 1946 .
FDR for most of it then Truman for the end At the beginning of World War 2 the President of the US was Franklin Delano Roosevelt. He died during the war on April 12, 1945. This made his vice president, Harry S. Truman, the new president. Truman was president when the war ended.
Franklin Delano Roosevelt (FDR) He died just before the war ended.
Which War? We've had many!
The cold war ended happily for the US while Reagan was President.
the president of he us after the war was James Madison
James Madison was still president when the war ended. James Monroe succeeded him in 1817.
So far there have been two world wars.The US President when the first one started was Woodrow Wilson; the US President when it ended was ... Woodrow Wilson.The US President when the second one started was Franklin Roosevelt. The US President when it ended was ... Harry Truman, but that's because he was Roosevelt's Vice-President and Roosevelt died shortly before the war was over.So a President can clearly remain in power "if a world war breaks out," though remaining in power if his own personal death "breaks out" is a considerably more difficult proposition.
The U.S. entered the war on April 6th, 1917. The U.S. president Woodrow Wilson created the Treaty of Versailles which ended the war.
Franklin Delano Roosevelt was the president until he died just before the war ended. The Vice President Harry S. Truman then became the President of the US and served until the end of the war. He also served as the president during the Korean War 5 years later.