Franklin Roosevelt was the first president to talk about the first one hundred days during a radio address on July 24, 1933. He reflected on the progress made during his first days in office, and the groundwork laid for the New Deal. Since then, the first one hundred days has become an important benchmark for measuring a new presidential administration. New presidents also use the first 100 days framework to highlight their priorities and demonstrate how they plan to move forward in their administration.
This guide has links to a number of U.S. Documents discussing the first 100 days of the presidency for numerous administrations—from Roosevelt to Biden.