Wikipedia:Selected anniversaries/January 7
January 7: Christmas (Christianity-Julian calendar).
- 1558 – Francis, Duke of Guise (pictured) retook Calais, England's last continental possession, for France.
- 1610 – Italian astronomer Galileo Galilei first observed three of Jupiter's natural satellites through his telescope: Io, Europa, and Callisto
- 1785 – Frenchman Jean-Pierre Blanchard and American John Jeffries became the first to cross the English Channel by balloon.
- 1924 – The International Hockey Federation, the global governing body for field hockey, was founded in Paris in response to the sport's omission from the 1924 Summer Olympics.
- 1979 – Phnom Penh, Cambodia fell to the People's Army of Vietnam, effectively ending the Khmer Rouge regime under Pol Pot.