Until 1933, the official inauguration day was March 4. Even then, first president of USA, George Washington, was not inaugurated until April 30 to give Congress time to count ballots and to allow the president-elect time to travel from Virginia to the nation’s then-capital, New York.
In 1933, Congress ratified the Twentieth Amendment to the U.S. Constitution in order to minimize the transition period. On January 20, 1937, Franklin D. Roosevelt became the first U.S. president sworn into office in January.