Who was President during the Great Depression and World War II?

Franklin D. Roosevelt was the President during both the Great Depression and World War II, overseeing his administration's response to these significant events. He took office in 1933, at the height of the Great Depression, and implemented a series of programs and reforms collectively known as the New Deal, aimed at providing relief, recovery, and reform to the American economy. Roosevelt's leadership style and proactive policies were instrumental in attempting to stabilize the nation during this devastating economic downturn.

As World War II began, Roosevelt played a crucial role in mobilizing the United States for war after the attack on Pearl Harbor in 1941. His administration focused on both military strategy and the home front efforts, coordinating resources and supporting the war through measures like the war economy and the Lend-Lease program.

The other figures mentioned held presidential office during different periods: Theodore Roosevelt was President from 1901 to 1909, Calvin Coolidge served from 1923 to 1929, and John F. Kennedy's term spanned from 1961 to 1963. None of these presidents were in office during the dual crises of the Great Depression and World War II, making Franklin D. Roosevelt the accurate choice for this question.