Serge Klarsfeld (born 17 September 1935) is a Romanian-born French activist and Nazi hunter known for documenting the Holocaust in order to establish the record and to enable the prosecution of war criminals.

Their son, Arno Klarsfeld [fr] (born 1965), became a human rights attorney and worked for Nicolas Sarkozy while he was minister of the interior.

In the years before 1989 and the dissolution of the Soviet Union, Klarsfeld and his wife frequently protested against the Eastern Bloc's support for the Palestine Liberation Organization and anti-Zionism.

[11] The Klarsfelds are notable in the postwar decades for having been involved in hunting and finding German Nazis and French Vichy officials responsible for the worst abuses of the Holocaust, in order to prosecute them for alleged war crimes.

In 1986, the Klarsfelds campaigned against Kurt Waldheim, a former United Nations Secretary-General who was elected president of Austria amid allegations that he had covered up his wartime activities as an officer in the Wehrmacht.

In 1996, during the warfare in the former Yugoslavia, the Klarsfelds joined the outcry against Radovan Karadžić and Ratko Mladić for alleged war crimes and genocide of Bosnian Muslims.

In December 2009, Klarsfeld defied an existing consensus within the Jewish community by saying that the beatification of Pope Pius XII was an internal matter of the Church.

In 1989, FFDJF was one of the groups to file a case against René Bousquet, head of the French Police in the Vichy government, for crimes against humanity.

Former French president Jacques Chirac acknowledged the nation's responsibility for the fate of Jews in its territory during the Second World War, and the government passed a law on 13 July 2000 to establish compensation for orphans whose parents were victims of antisemitic persecution.

[16] In January 2012, the Klarsfelds, along with prominent French-Armenian singer Charles Aznavour, director Robert Guédiguian, and philosophers Bernard-Henri Lévy and Michel Onfray, signed an appeal to the French Parliament to ratify a bill to establish penalties for people who deny the Armenian genocide.

[21][22] He argued that the National Rally was no longer a far-right party but a populist group that supports Jews and Israel, and claimed that the New Popular Front was dominated by La France Insoumise and Jean-Luc Mélenchon; he claimed that the radical left had moved to antisemitism and anti-Zionism, and that this represented "a danger", saying that Mélenchon was antisemitic and against Israel, and that he was "sure of this".

"[20] Le Monde headlined "Serge Klarsfeld short-circuits history to turn it upside-down", an article written by academic Michèle Cohen-Halimi, author Francis Cohen, and movie director Leopold von Verschuer.

Most of the deportees were sent from the transit camp at Drancy, ranging in age from newly born to 93 and originating from 37 countries, the most from France (22,193) and Poland (14,459), with a small number from the United States (10) and even one from Tahiti.

[25] Klarsfeld also wrote a preface to Une adolescence perdue dans la nuit des camps by Henri Kichka.

The 2001 documentary Marlene Dietrich: Her Own Song, a Turner Classic Movies Production about Dietrich mentions her support of Klarsfeld's anti-Nazi activities, while the 2008 drama Manhunt [fr] (La traque) was a French made-for-TV film, written by Alexandra Deman and Laurent Jaoui and directed by Laurent Jaoui, based on the Klarsfelds.