Throughout World War II, two American presidents were in power consecutively: Franklin D. Roosevelt and Harry Truman.
Franklin Delano Roosevelt
Franklin Delano Roosevelt was born in January 1882. He was the only child in a wealthy family, and he obtained his education through elite schools such as Groton and Harvard. He was an admirer of Theodore Roosevelt, his fifth cousin who was elected president in 1900. Roosevelt went to law school at Columbia University before becoming a clerk at a law firm. In 1910 he won a Senate seat and later named the assistant secretary to the US Navy by Woodrow Wilson who was President at the time. He married Anna Eleanor, the nice to Theodore Roosevelt in 1905. She had significant influence throughout his tenure. Before World War II broke out, he had warned the public about hardliner regimes of the Axis Powers. However, at the time he did not suggest that the United States should break from its Isolationist policy.
When the war started in 1939, Roosevelt urged Congress to review the neutrality acts to allow France and Britain to purchase American Weapons. In the following year when Germany captured France, he persuaded Congress to provide additional support towards Britain, which was combating the Nazi on its own.
Roosevelt ran for a third term in 1940, beating Wendell L. Wilkie by a significant margin. He increased support for Britain through the Lend-Lease Act. In his meeting with Winston Churchill on a Battleship off Canada, they formulated the Atlantic Charter. When Japan bombed Pearl Harbor in December 1941, Roosevelt declared war on Japan before a joint session of Congress. In the course of the war, he helped allied nations fighting the Axis. By 1944 the momentum of the war had turned in favor of the Allies, and the ailing Roosevelt won a fourth term as president.
Ending World War II
President Harry Truman led the United States through the final days of World War II. He was born in May 1884 in Missouri, and after high school, he did not attend college and began his early career as timekeeper, before becoming a clerk in a bank. Truman later returned to farming before enlisting in the National Guard. During World War I, he led Battery D as Captain through the successful Meuse-Argonne campaign. After the war, he went into business but failed. He was later elected into a legal administrative position and later as a Senator in 1934.
In Senate, he earned a reputation of a man of integrity after he helped push legislation that placed tighter federal regulation on railroads. He served as Vice president to Franklin D. Roosevelt for 82 days before Roosevelt's death. In Truman's initial months as President, he announced the Surrender by Germany and ordered dropping of Atomic Bombs on Nagasaki and Hiroshima, bringing World War II to an end.