The United Nations War Crimes Commission was established at a meeting held at the Foreign Office in London on October 20, 1943.  The Commission, operating from a secretariat in London, consisted of government representatives appointed by the 17 member countries:  Australia, Belgium, Canada, China, Czechoslovakia, Denmark, France, Greece, India, Luxembourg, the Netherlands, New Zealand, Norway, Poland, the United Kingdom, the United States and Yugoslavia.  The first official meeting took place on January 11, 1944, and the Commission continued its activities until the end of March 1948, and was dissolved in May of that year.  

In addition to the main commission, a separate Far Eastern sub‐ commission was established at the suggestion of the Chinese ambassador.  This sub‐commission was initially based in Chongqing, and later, Nanjing, operating from November 1944 until March 1947. The primary activities of the Commission were to identify and prepare lists of alleged war criminals, and to help formulate the legal machinery used by the member countries to apprehend, bring to trial and prosecute war criminals.   

For the task of identifying alleged war criminals, the Commission relied on evidence supplied by member countries, through their respective National Offices, which was reviewed and examined by the Commission.  Once the Commission determined that there was sufficient evidence to prosecute alleged war criminals, it compiled lists of such individuals, sending these lists back to the National Offices, so that the individuals could be arrested and prosecuted by the member governments, usually in the country where the war crimes had taken place.  The Commission itself, however, took no other part in the actual detention of the individuals or the prosecution of their cases, which were left to the member governments to pursue.  

In regard to the legal framework for the prosecution of alleged war criminals, the Commission provided guidance to member states and formulated recommendations for how the cases could be prosecuted, and in doing so, helped shape the development of international law in areas such as jurisdiction, extradition, personal responsibility for acts of State, the protection of human rights of civil populations against violations by their own government and other similar issues.

[Source:  original finding aid of the United Nations War Crimes Commission, Predecessor Archival Group 3, at UN‐ARMS; and the article on the UNWCC in Federal Records of World War II:  Volume 1, Civilian Agencies, National Archives of the United States, p. 1059]