A crime against humanity is an act of persecution against a group so heinous as to warrant punishment under international law.
The term was first used in the preamble of the Hague Convention of 1907, and subsequently used during the Nuremberg trials as a charge for actions such as the Holocaust which did not violate a specific treaty but were deemed to require punishment.
The term has been criticized for being extremely vague and for being politically defined. For example, Nazi attempts to eliminate certain ethnic groups are widely recognized as having been crimes against humanity, yet Soviet persecution of certain economic groups are not. The systematic persecution of African people by the South African apartheid government is e.g. recognized as a crime against humanity by the United Nations since 1966.
In its Article 7, the treaty establishing the International Criminal Court in 2003 says:
- For the purpose of this Statute, "crime against humanity" means any of the following acts when committed as part of a widespread or systematic attack directed against any civilian population, with knowledge of the attack: (a) Murder; (b) Extermination; (c) Enslavement; ...  (http://www.preventgenocide.org/law/icc/statute/part-a.htm#2)
A list of crimes against humanity
(incomplete and subjective: whether an act is defined as crime against humanity may depend on the political view.)
- 1904: The German colonial power strike down the uprising of the Herero and Nama in the territory today known as Namibia. Large parts of the Herero und Nama die with thurst; survivers are forced to heavy labour; between 25,000 to 100,000 (probably 65,000) Herero and 10,000 Nama die
- 1915-1918: The use of poison gas in the first world war.
- 1915-1916: The Turkish genocide on the Armenians: about 1.5 million people die
- 1922: The socalled Asia minor catastrophe: turkish troups destroy Smyrna and kill tens of thousands of greek civilians
- 1937-1945: The Japanese war againstChina, which involved serious crimes against the Chinese civilian population
- 1933-1945: German Nazis kill 6 million Jews, 500,000 Sinti und Roma, homosexuals, social democrats and communists in Europe; see also (holocaust)
- 1933-1945: the socalled "Aktion T 4" (euthanasia-program), mass morder on about 80,000 handicapped and chronically ill people. Among them many children and "foreign workers"
- 1938-1943: German armed forces systematically displace and kill Czech, Polish, Russian people (among others) during the "war of extermination" ("Vernichtungskrieg") in Europe, Africa and Asia; see also second world war)
- 1944-1945: Allied forces systematically bomb German residental areas in the second world war
- 1945-1949: Displacement of ethic Germans from Eastern Prussia and other former German Eastern territories (Bierut-decree), Czechoslovakia (Beneš-Decree) and other Eastern European countries following the second world war.
- 1917-1953: Numerous crimes by the communist system in the Soviet Union, installation of extensive penal camps "archipelago GULAG" (see also Stalinism and Kurapaty.
- 1945: The United States drop nuclear bombs on Nagasaki and Hiroshima, and a napalm bomb on Tokio
- 1962-1975: The United States use napalm and other chemical warfare in Vietnam
- 1965: The coup government of the new Indonesian government kills approximately 100,000 to 1,000,000 (presumably) partisans of the communist party
- 1966: The systematic persecution of African people by the apartheid system in South Africa
- 1966-1976: Mao Zedong's "cultural revolution" in China goes hand in hand with political cleaning; several million people die in China and autonomous areas.
- 1974-1989: The communist government of Rumania under the leadership of Nicolae Ceausescu systematically persecutes political enimies and plans the so-called "village destruction program". He also sets up "death homes" for handicapped, chronically ill and unwanted children. People older then 65 are refused to get medical help; see also Elena Ceausescu and Cighid.
- 1975-1979: Under the leadership of Pol Pot the Red Khmer committ mass morder in Cambodia
- 1973-1989: Augusto Pinochet and his military dictatorship assassin political opponents and torture tens of thousands of people in Chile
- 1976-1982: The military dictatorship in Argentina assassins political opponents and tortures in Argentina
- 1975-1981 Genocide in East Timor (the conflict holds in unreleaved intensity until 1998/1999)
- 1983-ongoing: Several million black Africans die in a tribal genocide in Sudan
- 1988: On March 16th Saddam Hussein launches a poison gas attack against the kurdish city of Halabdscha in the North of Irak. About 5,000 people die (almost solely civilians).
- 1994: During the civil war in Ruanda between Hutu and Tutsi 500,000 poeple die
- 1991-1999: Various crimes of war take place during the Bosnian war on each side.
- 1996-2001: Various violations against human rights by the radical-islamic Taliban-regime in Afghanistan
- 1949-heute: Various violations against human rights by the the Republic of China; (see Tibet, East Turkestan and Southern Mongolia.
See also: Genocide, mass murder, war crime, crime against peace, state terrorism, ethnic cleansing, Nuremberg Principles, and Rome Statute of the International Criminal Court.