31-The first Easter is celebrated by Christians, according to calendar-maker Dionysius Exiguus
1436-Florence Cathedral (Cattedrale di Santa Maria del Fiore), started in 1296, is consecrated by Pope Eugene IV. Designed by Filippo Brunelleschi with support from Cosimo de' Medici, it features the largest dome in the world at the time.
1807-British Parliament abolishes the slave trade throughout the British Empire; a penalty of £120 per slave is introduced for ship captains
1895-Italian troops invade Abyssinia (Ethiopia)
1943-Akira Kurosawa's debut film "Sanshiro Sugata" is released
1960-First guided missile launched from a nuclear powered submarine (USS Halibut)
1965-Martin Luther King Jr. leads 25,000 to state capitol in Montgomery, Alabama
1976-Argentine military junta bans leftist political parties