- 1893: Crash of the New York stock market.
- 1905: Mutiny on the battleship Potemkin.
- 1950: The United States decided to send troops to Korea to fight in the Korean War.
- 1954: The world's first nuclear power station opened in Obninsk, near Moscow
- 1957: Hurricane Audrey kills 500 people in Louisiana and Texas.
- 1969: The Stonewall incident marks the start of the gay rights movement in the US.
- 1985: Route 66 ceases to be an official highway.
- 363: emperor Julian
June 27 is also:
- National HIV Testing Day (in which country ?)
- Gay Freedom Day (in which country?)