Dr Jan Karski (24 April 1914 - 13 July 2000), Polish resistance fighter, was born in Lodz as Jan Kozielewski. He received a Master's degree in Law and Diplomatic Science in 1935 at the University of Lwów. He completed his education between 1936 and 1938 in different diplomatic posts in Germany, Switzerland and Britain, and went on to join the Diplomatic Service.
Mobilised at the outbreak of war in 1939, Karski was taken prisoner by the Soviet Army. Two months later, in November, he escaped from a prisoner-of-war camp and returned to the General Government in German-occupied Poland. There he joined the underground Home Army (AK). His knowledge of foreign languages proved to be very useful when he was sent as a courier between the Polish government-in-exile in London and the AK in Poland. As a courier, Karski made several secret trips between France, Britain and Poland.
In 1942 and 1943 Karski reported to the Polish, British and American governments on the situation in Poland, especially the destruction of the Warsaw Ghetto and the methodical extermination of the Jews.
Karski also entered a concentration camp in 1942 disguised in the uniform of a camp guard, and believed it to be the Belzec death camp. However, the descriptions he gave are incompatible with what is known about Belzec. His biographers Wood and Jankovski later proposed that Karski had actually been in the Izbica Lubelska concentration camp rather than in Belzec. Many historians have accepted this theory, as did Karski himself.
In July 1943, Karski personally reported to president Franklin Roosevelt about the situation in Poland. He also spoke with many other government and civic leaders in the United States, but without success. Most of those he spoke to did not believe him, or supposed that his testimony was much exaggerated or propaganda from the Polish government in exile.
After the war Karski was unable to return to Poland and made his home in the United States and began his studies at Georgetown University, where he received a PhD in 1952. He taught at Georgetown for 40 years in the areas of East European affairs, comparative government and international affairs. In 1954, he became an American citizen after being deprived of his citizenship by the Polish communist regime.
In Story of a Secret State (1944), Karski related his experiences in wartime Poland. In 1985, he published The Great Powers and Poland. In 1996, Thomas E. Wood and Stanislaw M. Jankowski published Jan Karski: How One Man Tried to Stop the Holocaust.
After the fall of Communism in Poland, Karski's wartime role was officially acknowledged there. He received the Order of the White Eagle (the highest Polish civil decoration) and the Order Virtuti Militari (the highest military decoration awarded for bravery in combat).
In honour of his efforts on behalf of Polish Jews, Karski was made an honorary citizen of Israel. In Jerusalem a tree bearing his name was planted in the Alley of the Righteous Among the Nations. Georgetown University, Oregon State University, Baltimore Hebrew College, Hebrew College of America, Warsaw University, Maria Curie-Sklodowska University, and Lodz University all awarded him honorary doctorates. He died in Washington in July 2000.