The United States formally declared war on Mexico after several days of fighting.
Mary Queen of Scots was defeated at the Battle of Langside and immediately fled to North England.
Louis Armstrong and his orchestra recorded the New Orleans's jazz classic, When the Saints Go Marching In, on Decca Records.
Winston Churchill gave his first speech as prime minister: "I have nothing to offer but blood, toil, tears and sweat."
Tennis male chauvinist Bobby Riggs defeated Margaret Smith Court, 6-2, 6-1 in front of a world-wide television audience. He would lose to Billie Jean King later that year.
Pope John Paul II was shot and wounded by Mehmet Ali Agca as he drove through a crowd in St. Peter's Square, Rome.
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