MORE EVENTS ON THIS DAY

2017: Irish politician Martin McGuinness—who, as a member of Sinn Féin, the political wing of the Irish Republican Army (IRA), played an influential role in negotiating the Good Friday Agreement (Belfast Agreement) of 1998—died at age 66. [ Sort fact from fiction in our quiz about famous Europeans.]

2006: Twitter cofounder Jack Dorsey sent the first public tweet, which read “just setting up my twttr.” [Test your knowledge of tech companies.]

1990: After 106 years of German and South African rule, Namibiabecame independent. [ Sort fact from fiction in our Africa quiz.]

1980: U.S. President Jimmy Carter announced that the United States was boycotting the Summer Olympics in Moscow to protest the Soviet invasion of Afghanistan. [ Take our Olympic history quiz.]

1965: American civil rights activists led by Martin Luther King, Jr., began a protest march from Selma to Montgomery, Alabama. [Learn about 10 milestones in civil rights history.]

1880: German painter Hans Hofmann , an influential art teacher and a pioneer in the use of improvisatory techniques whose work paved the way for American painters to develop Abstract Expressionism, was born. [Test your knowledge of artistic styles and techniques.]