Polish Historian, Educator, Author. He is best known for his knowledge of Polish history, being published on that subject, and being a respected professor at Warsaw University. Born in a family of Jewish ancestry, he was the oldest son of Julian and Eleonora Handelsman. He was well-educated: First, received in 1904 a law degree from the Russian University in Warsaw, then Humboldt University of Berlin, Germany where he was dismissed for his liberal political activities; but went on to study in Paris, France, Vienna, Switzerland and London, England. He received his doctorate in 1908. During World War I, he returned to Warsaw University to teach modern history. Becoming a respected historian, he was appointed to the Polish Academy of History. Between 1918 and 1939, he was also the editor-in-chief of the Historical Review and the head of a Commission for the Atlas of History of Polish Lands from 1920 to 1935. He was also a member of the Academy of Moral and Political Sciences in Paris and the London-based Royal Society. He later worked on a monumental and unfinished biography of Prince Adam Jerzy Czartoryski, a central figure in Polish political life in the first half of the nineteenth century, who wrote popular accounts of Polish history and of the development of the idea of nationalism. Handelsman was very interested in all aspects of 19th-century Polish political history, particularly Czartoryski's Hôtel Lambert Circle, a Paris haven for Polish exiles. Strangely, he had no real interest in Jewish history, for which he was attacked by Jewish activists. At the same time, he did encourage Jewish historical scholarships. He was one of the editors of "Przegląd Historyczny". At the outbreak of World War II, he hid himself from the Germans because of his Jewish ancestry. Nazi Germany was attempting to eradicate the Polish culture; he worked with the underground education system to prevent this from happening. He was a professor in the underground Warsaw University and part of the Polish resistance in Bureau of Information and Propaganda of the Headquarters of Home Army. He was arrested by the Gestapo on August 14, 1944 and sent to Gross-Rosen Concentration Camp, which was located on the border of Poland and Germany. Later, he was transferred to Nordhausen-Dora Concentration Camp in Germany where he was murdered on March 20, 1945. On April 11, 1945, US troops freed the remaining prisoners. One in three of the roughly 60,000 prisoners who were sent to this camp did not survive. He was married to Jadwiga Kernbaum and they had two children. A memorial service was held for him in the library of Warsaw University on January 3, 1946. In his lifetime, he published a total of 27 books plus newspaper and magazine articles, which have been translated into five languages with at least three of his books still in print. His 1913 text "The Development of Modern Nations" had the last edition printed in 1973 and in three languages.