The present Convention was occasioned by the fear, which grew in the mid-1960's, that German war criminals of World War II, who had not yet been apprehended, might escape prosecution because of the expiration of the periods of limitation applicable to their crimes. The Convention was prepared by the Human Rights Commission and thereafter adopted and opened for signature by the General Assembly of the United Nations. It will be noted that the definition of "crimes against humanity" was broadened compared with the definition contained in the Charter of the Nüremberg Tribunal.
D.Schindler and J.Toman, The Laws of Armed Conflicts, Martinus Nihjoff Publisher, 1988, pp.925-928.