Today is the 206th day of the year, with 159 days remaining.
306 - Constantine I is proclaimed Roman emperor by his troops.
864 - The Edict of Pistres of Charles the Bald, orders defensive measures against the oncoming Vikings.
1261 - The city of Constantinople is recaptured by Nicaean forces under the command of Alexios Strategopoulos, re-establishing the great Byzantine Empire.
1536 - Sebastian de Belalcazar, on his search for El Dorado, founds the city of Santiago de Cali.
1603 - James VI of Scotland is crowned as the King of England. This brings the Kingdom of England and the Kingdom of Scotland into personal union. There will not be political union until 1707.
1759 - In Western New York, during the French and Indian War, British forces capture Fort Niagara from the French, and they subsequently abandon Fort Rouille.
1780 - General Horatio Gates takes over command of the southern army based in North Carolina during the American Revolution.
1788 - Wolfgang Mozart finally completes Symphony No. 40 in G minor.
1797 - Horatio Nelson loses more than 300 men and his right arm during the failed conquest attempt on Tenerife.
1814 - Battle of Lundy's Lane, during the War of 1812. Reinforcements arrive near Niagara Falls for General Riall's British and Canadian forces, and bloody, all-night battle ensues with Jacob Brown's American troops. The Americans will retreat to Fort Erie.
1832 - The first recorded railroad accident occurs. Four people are thrown off a vacant car on the Granite Railway near Quincy, Massachusetts. During their return trip to their boarding location, a cable snapped and flipped the car throwing the riders off of a 34-foot cliff. One man is killed and the others are seriously injured.
1861 - The United States Congress passes the Crittenden-Johnson Resolution, stating that the war is being fought to preserve the Union and thus not to put an end to slavery.
1866 - Congress passes legislation authorizing the military rank of Five-star General of the Army. Ulysses S. Grant becomes the first man promoted to this rank.
1868 - Wyoming becomes a United States territory.
1898 - After over two months of heavy bombardment, the United States invasion of Puerto Rico begins with troops led by General Nelson Miles landing at the harbor of Guanica.
1909 - Louis Bleriot makes the first flight across the English Channel in a light and sleek monoplane. He travels from Calais to Dover in thirty-seven minutes.
1915 - Royal Flying Corps Captain Lanoe Hawker becomes the first British military aviator to earn the Victoria Cross. He shot down two German two-seat observation aircraft in one day.
1917 - In Paris, France, the exotic dancer Mata Hari, is sentenced to death by a French court for spying on behalf of Germany during the First World War.
1934 - The Nazis assassinate the Austrian Chancellor Engelbert Dollfuss, because of his involvement in a failed coup attempt.
1943 - Benito Mussolini is forced out of office by his own Italian Grand Council and is replaced by Pietro Badoglio.
1944 - Operation Spring occurs, in one of the bloodiest days for the First Canadian Army losing 1,000 men wounded or missing, and 500 troops killed.
1946 - An atomic bomb is detonated underwater in the lagoon of Bikini atoll, codenamed Operation Crossroads.
1954 - Walter Peyton, National Football League running back with the Chicago Bears, was born today.
1965 - Bob Dylan decides to use an electric guitar at the Newport Folk Festival. He plugs in, and signals a major change for both folk and rock music.
1969 - President Richard Nixon declares his Nixon Doctrine. Thus stating that the United States now expects its Asian allies to take care of their own military defense. This is essentially the start of the "Vietnamization" part of the war.
1978 - Louise Brown, the world's first "test-tube baby" is born in a Oldham General Hospital, Greater Manchester, United Kingdom. The development came from the process of "in vitro fertilisation."
1987 - A Salyut 7 cosmonaut, named Svetlana Savitskaya, becomes the first woman to perform a space walk.