The Nuremberg Trials were Military Tribunals...
Here's a link to the key players:
http://www.courttv.com/archive/casefiles/nuremberg/participants.htmlAlso, there's this:
The Creation of the Tribunal and the Law Behind It
Creation of the International Military Tribunal
During World War II, the Allies and representatives of the exiled governments of occupied Europe met several times to discuss post-war treatment of the Nazi leaders. Initially, most of the Allies considered their crimes to have been beyond the scope of human justice -- that their fate was a political, rather than a legal, question.
Winston Churchill, for example, said in 1944 that they should be "hunted down and shot." The French and Soviets also supported summary executions. The Americans, however, pushed for a trial. (A faction within the U.S. government led by Secretary of War Henry L. Stimson had won a domestic battle over the U.S. position on punishment of the Nazis. The other faction, led by Henry Morgenthau, the Jewish secretary of the Treasury, supported a harsh plan designed to prevent Germany from ever rising again as an industrial power.)
In August 1945, the British, French, Americans and Soviets, meeting in London, signed the agreement that created the Nuremberg court, officially the International Military Tribunal, and set ground rules for the trial. The London Charter of the International Military Tribunal, was named to avoid using words such as "law" or "code" in an effort to circumvent the delicate question of whether the trial would be ex post facto.
The London Charter set down the rules of trial procedure and defined the crimes to be tried. (It did not define the term "criminal organizations," although six organizations were indicted under the charter.)
The defendants were charged not only for the systematic butchering of millions of people, but also for planning and carrying out the war in Europe.
http://www.courttv.com/archive/casefiles/nuremberg/law.html