1997 The United Kingdom returned Hong Kong to the People's Republic of China

1921 The Communist Party of China (CPC) was formed, and Chen Duxiu was elected its leader

1807 Innovation of the steamboat

1940 Winston Churchill became British Prime Minister, replacing Neville Chamberlain

1836 Spain recognized the independence of Mexico by signing the Santa María–Calatrava Treaty

2003 The Spirit Rover was launched by NASA to start the Mars Exploration Rover mission

1963 President John F. Kennedy signed the United States Equal Pay Act into law

1901 Guglielmo Marconi sent and received the first wireless message across the Atlantic Ocean

1903 Innovation of the aeroplane

1926 John Logie Baird gave the first public demonstration of a live television system

1945 International Monetary Fund was formally established by 29 member countries

1932 Radio City Music Hall opened in New York City

1965 United States President Lyndon B. Johnson signed the Voting Rights Act into law

1964 United States President Lyndon B. Johnson signed the Civil Rights Act into law

1895 German physicist Wilhelm Conrad Röntgen discovered X-Rays

1808 The slave trade became illegal when the United States enacted a law banning the importation of slaves

1924 Astronomer Edwin Hubble formally announced that the Milky Way is just one of many galaxies in the universe