Kouchner's paternal grandparents were Russian-born Jews who escaped the pogroms by immigrating to France, but perished decades later in Auschwitz.

[3] Kouchner began his political career as a member of the French Communist Party (PCF), from which he was expelled in 1966 for attempting to overthrow the leadership.

Together with Judge Andrée Ruffo, Kouchner established the International Bureau for Children's Rights (IBCR), a non-governmental organization based in Montreal, in 1994.

On 15 July 1999, pursuant to Security Council Resolution 1244, UN Secretary General Kofi Annan nominated Kouchner as the second UN Special Representative and Head of the United Nations Interim Administration Mission in Kosovo (UNMIK).

[7] During 18 months, he led UN efforts to create a new civil administration and political system replacing the Serbian ones, and to rebuild the economy shattered by the Kosovo War.

In 2005, Kouchner was a candidate for the position of United Nations High Commissioner for Refugees (UNHCR), but lost the appointment in favor of former Portuguese Prime Minister, António Guterres, who was nominated by then-UN Secretary-General Kofi Annan.

In 2007, the European Commission appointed Kouchner as its representative on the International Independent Group of Eminent Persons (IIGEP), a group of individuals nominated by international donor countries and the government of Sri Lanka, vested with a wide mandate to observe all investigations and inquiries conducted by and on behalf of the Commission of Inquiry into alleged human rights abuses in Sri Lanka.

[11] In early 2003, he pronounced himself in favour of removing Saddam Hussein as President of Iraq,[11] arguing that interference against dictatorship should be a global priority, and continued to say that now, the focus should be on the actual people themselves, and that they are the only ones who could answer yes or no to war.

[16] In 2012, Kouchner co-signed the George Soros call for a strengthening of the European prerogatives as an answer to the eurozone crisis.

[18] He stated that France was committed to a diplomatic resolution and that no military action was planned, but that an Iranian nuclear weapon would pose "a real danger for the whole world".

[18] The chief UN nuclear inspector Mohamed ElBaradei, the head of the International Atomic Energy Agency indirectly responded to Kouchner by characterizing talk of attacking Iran as "hype", saying the use of force should only be considered as a last resort and only if authorized by the UN Security Council.

[22] Kouchner denounced statements by Pope Benedict XVI claiming that condoms promoted AIDS, saying they were "the opposite of tolerance and understanding".