In 1646, the philosopher, mathematician, lawyer and diplomat Gottfried Leibniz was born in Leipzig.
In 1870, the United States Department of Justice came into being.
In 1892, the Amalgamated Association of Iron and Steel Workers went on strike against the Carnegie Steel Company. The strike occurred in Homestead, Pennsylvania, included gun battles between the strikers and agents of the Pinkerton National Detective Agency and Alexander Berkman's attempted assassination of Henry Clay Frick. The strike ended as a defeat for the strikers and is known today as the Homestead Strike.
In 1896, the abolitionist Harriet Beecher Stowe died.
In 1915, the blues musician Willie Dixon was born in Vicksburg, Mississippi.
In 1916, the Battle of Albert initiated what became known as the First Day on the Somme in the Battle of the Somme. The battle was an offensive conducted by the British and French armies against the German army. The Somme campaign stands today as one of the bloodiest in history.
In 1921, the Communist Party of China formed.
In 1967, the European Community came into existence.
In 1968, sixty-two countries signed the Nuclear Non-Proliferation Treaty.
In 1974, the Argentinean politician Juan Perón died.
In 1990, East Germany accepted the Deutsche Mark as its currency, thus uniting the East and West German economies.
In 1991, the Warsaw Pact dissolved.
1997, the People's Republic of China regained sovereignty over Hong Kong.