In 1533: Pope Clement VII excommunicated England’s King Henry VIII.
In 1804: Vice President Aaron Burr mortally wounded former Treasury Secretary Alexander Hamilton in a pistol duel near Weehawken, N.J.
In 1864: Confederate forces led by Gen. Jubal Early began an invasion of Washington, D.C., turning back the next day.
In 1952: The Republican National Convention, meeting in Chicago, nominated Dwight D. Eisenhower for president and Richard M. Nixon for vice president.
In 1977: The Medal of Freedom was awarded posthumously to the Rev. Martin Luther King Jr. in a White House ceremony.