- 33 AD: The crucifixion and resurrection of Jesus Christ, according to the Christian faith.
- 325 AD: The Council of Nicaea establishes the date of Easter as the first Sunday after the full moon following the vernal equinox.
- 1095 AD: Pope Urban II delivers a speech at the Council of Clermont, calling for the First Crusade to retake the Holy Land from Muslim control.
- 1187 AD: Saladin, the Muslim leader of Egypt and Syria, retakes Jerusalem from the Crusaders.
- 1204 AD: The Fourth Crusade captures Constantinople, the capital of the Byzantine Empire.
- 1517 AD: Martin Luther posts his 95 Theses, sparking the Protestant Reformation.
- 1620 AD: The Pilgrims land at Plymouth Rock in present-day Massachusetts, United States.
- 1775 AD: The Battles of Lexington and Concord mark the beginning of the American Revolutionary War.
- 1865 AD: The American Civil War ends with the surrender of the Confederate army.
- 1916 AD: The Easter Rising, an uprising against British rule in Ireland, takes place in Dublin.
- 1945 AD: Adolf Hitler commits suicide as Allied forces close in on Berlin, marking the end of World War II in Europe.