On April 18th, 1521, the trial of Martin Luther began its second day and Luther refused to recant his teachings despite the risk of excommunication.
Also on this day in 1942, the Doolittle Raid on Japan was carried out. Tokyo, Yokohama, Kobe, and Nagoya were bombed. While strategically ineffective, the raid had a huge impact on the moral of the United States, showing that Japan was not “out of reach” like they believed.