Dia dos Namorados in Brazil
1240 – The Disputation of Paris began in the court of King Louis IX, in which four rabbis defended the Talmud against Nicholas Donin's accusations of blasphemy.
1381 – The first mass protest in the Peasants' Revolt began in Blackheath, England, caused by political and socioeconomic tensions due to the Black Death and high taxes as a result of the Hundred Years' War.
1942 – On her thirteenth birthday, Anne Frank began keeping her diary during the Nazi occupation of the Netherlands.
1967 – The U.S. Supreme Court delivered its decision in the landmark civil rights case Loving v. Virginia, striking down laws restricting interracial marriage in the United States.
1987 – Cold War: During a speech (pictured) at Berlin's Brandenburg Gate by the Berlin Wall, U.S. President Ronald Reagan challenged Soviet leader Mikhail Gorbachev to "tear down this wall!"