Raphael Lemkin was a lawyer of Polonized-Jewish descent who is best known for coining the word genocide and initiating the Genocide Convention. Lemkin coined the word genocide in 1943 or 1944 from the rooted words genos (Greek for family, tribe, or race) and -cide (Latin for killing).
In 1933 Lemkin made a presentation to the Legal Council of the League of Nations conference on international criminal law in Madrid, for which he prepared an essay on the Crime of Barbarity as a crime against international law. The concept of the crime, which later evolved into the idea of genocide, was based on the Armenian Genocide and prompted by the experience of Assyrians massacred in Iraq during the 1933 Simele massacre. In 1934 Lemkin, under pressure from the Polish Foreign Minister for comments made at the Madrid conference, resigned his position and became a private solicitor in Warsaw. While in Warsaw, Lemkin attended numerous lectures organized by the Free Polish University, including the classes of Emil Stanisław Rappaport and Wacław Makowski.
In 1944, the Carnegie Endowment for International Peace published Lemkin's most important work, entitled Axis Rule in Occupied Europe, in the United States. This book included an extensive legal analysis of German rule in countries occupied by Nazi Germany during the course of World War II, along with the definition of the term genocide. Lemkin's idea of genocide as an offense against international law was widely accepted by the international community and was one of the legal bases of the Nuremberg Trials. In 1945 to 1946, Lemkin became an advisor to Supreme Court of the United States and Nuremberg Trial chief counsel Robert H. Jackson.