The 20th Amendment, ratified in 1933, moved presidential inaugurations from March 4 to January 20 to shorten the lame-duck period between election and taking office. Roosevelt's 1937 swearing-in, delivered in driving rain, became the first to follow the new date, fixing it permanently in American civic life.
For nearly a century and a half, incoming presidents waited four long months after election day before assuming power, a gap that had once made sense when travel was slow but by the 1930s left the country rudderless during crises like the Great Depression's darkest winter of 1932-33. The 20th Amendment, championed partly by Senator George Norris of Nebraska, closed that gap by moving the date to January 20.
Roosevelt stood in a downpour on the Capitol's East Portico to take the oath, his second of four. Reporters noted he refused an umbrella, letting rain soak his coat as he delivered an address warning that 'the test of our progress is not whether we add more to the abundance of those who have much, it is whether we provide enough for those who have too little.'
Every presidential inauguration since, barring a Sunday shift to the 21st, has landed on this date, making January 20 one of the most quietly consequential days on the American political calendar.