Franklin Delano Roosevelt the longest serving president in U.S. history successfully guided Americans through two of the worst crises ever. He succeeded where others had failed in pulling the country back from the brink of collapse during the Great Depression. He lifted Americans spirits and turned them away from fear and defeatism. Then came the horrors and devastation of World War II. The brilliant and courageous Roosevelt proved to be an outstanding commander in chief, leading the world to victory over the powers of evil.