221 – Roman emperor Elagabalus adopts his cousin Alexander Severus as his heir and receives the title of Caesar.
699 – En no Ozuno, a Japanese mystic and apothecary who will later be regarded as the founder of a folk religion Shugendō, is banished to Izu Ōshima.
1407 – Ulrich von Jungingen becomes Grand Master of the Teutonic Knights.
1740 – A combined force of Spanish, free blacks and allied Indians defeat a British garrison at the Siege of Fort Mose near St. Augustine during the War of Jenkins’ Ear.
1794 – French Revolutionary Wars: Battle of Fleurus marked the first successful military use of aircraft.
1843 – Treaty of Nanking comes into effect, Hong Kong Island is ceded to the British “in perpetuity.”
1870 – The Christian holiday of Christmas is declared a federal holiday in the United States.
1886 – Henri Moissan isolates elemental Fluorine for the first time.
1909 – The Science Museum in London comes into existence as an independent entity.
1924 – The American occupation of the Dominican Republic ends after eight years.
1927 – The Cyclone roller coaster opens on Coney Island.
1934 – United States President Franklin D. Roosevelt signs the Federal Credit Union Act, which establishes credit unions.
1936 – Initial flight of the Focke-Wulf Fw 61, the first practical helicopter.
1948 – The first supply flights are made in response to the Berlin Blockade.
The Cyclone, a historic wooden rollercoaster, opened June 26, 1927 in Coney Island.
1948 – Shirley Jackson’s short story The Lottery is published in The New Yorker.
1960 – Madagascar gains its independence from France.
1963 – U.S. President John F. Kennedy gave his “Ich bin ein Berliner” speech, underlining the support of the United States for democratic West Germany shortly after Soviet-supported East Germany erected the Berlin Wall.
1974 – The Universal Product Code is scanned for the first time to sell a package of Wrigley’s chewing gum at the Marsh Supermarket in Troy, Ohio.
1975 – Two FBI agents and a member of the American Indian Movement are killed in a shootout on the Pine Ridge Indian Reservation in South Dakota; Leonard Peltier is later convicted of the murders in a controversial trial.
2000 – The Human Genome Project announces the completion of a “rough draft” sequence.
2000 – Pope John Paul II reveals the third secret of Fátima.
2003 – The U.S. Supreme Court rules in Lawrence v. Texas that gender-based sodomy laws are unconstitutional.
2013 – The U.S. Supreme Court ruled, 5-4, that Section 3 of the Defense of Marriage Act is unconstitutional and in violation of the Fifth Amendment to the United States Constitution.
2015 – The U.S. Supreme Court ruled, 5-4, that same-sex couples have a constitutional right to marriage under the 14th Amendment to the United States Constitution.
Births
1824 – William Thomson, 1st Baron Kelvin, Irish-Scottish mathematical physicist (Kelvin Scale) and engineer (transatlantic telegraph)
1961 – Greg LeMond, US professional road cyclist (Tour de France winner-1986, 1989, 1990
Deaths
1541 – Francisco Pizarro, Spanish conquistador who conquered the Inca Empire
1997 – Don Hutson, first NFL wide receiver
Edited from various sources including historyorb.com, the NYTimes.com
Wikipedia and other internet searches