The Black September Organization (BSO) was a Palestinian terrorist organization founded in 1970. It was responsible for the assassination of the Jordanian prime minister Wasfi Al-Tal, kidnapping and murder of eleven Israeli athletes and officials, and the Munich Massacre, their most publicized event. These events led to the creation of permanent, professional, and military-trained counter-terrorism forces of major European countries, like GSG9 and GIGN, and the reorganization and specialization of already standing units like the Special Air Service of the United Kingdom.
Black September perpetrated a number of other attacks during their existence, including:
- December 1971: the attempted assassination of Zeid al Rifai, Jordan's ambassador to London and former chief of the Jordanian royal court;
- 6 February 1972: sabotage of a West German electrical installation and gas plants in Ravenstein and Ommen in the Netherlands and in Hamburg in West Germany;
- 8 May 1972: hijacking of a Belgian aircraft, Sabena Flight 572, flying from Vienna to Lod.
- September and October 1972: dozens of letter bombs were sent from Amsterdam to Israeli diplomatic posts around the world, killing Israeli Agricultural Counsellor Ami Shachori in Britain.
- 1 March 1973: Attack on the Saudi Embassy in Khartoum, Sudan: 10 hostages were held at the Saudi Arabian embassy, five of them diplomats. The US ambassador, the US deputy ambassador, and the Belgian chargé d'affaires were murdered. The remaining hostages were released. A 1973 United States Department of State document, declassified in 2006, concluded: "The Khartoum operation was planned and carried out with the full knowledge and personal approval of Yasser Arafat."
- 2 March 1973: New York bomb plot
- 5 August 1973: two Palestinian militants claiming affiliation with Black September open fire on a passenger lounge in Athens now closed Ellinikon International Airport, killing three and wounding 55. A Lufthansa Boeing 737 is hijacked from Rome in December 1973 to demand that the gunmen be freed from Greek custody.