April 7: National Beer Day in the United StatesArtist's conception of 2001 Mars Odyssey1655 After a conclave lasting eighty days, the College of Cardinals elected Fabio Chigi as Pope AlexanderVII (pictured).1945 World WarII: U.S. forces sank the Japanese battleship Yamato during Operation KikusuiI in the East China Sea.1994 Rwandan Civil War: The Rwandan genocide began a few hours after the assassination of President Juvnal Habyarimana, with hundreds of thousands killed in the following 100 days.1995 First Chechen War: Russian paramilitary troops began a massacre of hundreds of civilians in Samashki, Chechnya.2001 NASA's 2001 Mars Odyssey (artist's conception pictured), the longest-surviving continually active spacecraft in orbit around a planet other than Earth, launched from Cape Canaveral.BerengarI of Italy (d.924)Martha Ray (d.1779)Joseph Lyons (d.1939)Dave Arneson (d.2009)More anniversaries: April 6April 7April 8ArchiveBy emailList of days of the yearAbout