The Thirteenth Tribe is a 1976 book by Arthur Koestler advocating the Khazar hypothesis of Ashkenazi ancestry, the thesis that Ashkenazi Jews are not descended from the historical Judeans and Israelites of antiquity, but from Khazars, a Turkic people who allegedly mass-converted to Judaism. Koestler hypothesized that the Khazars after their conversion in the 8th century migrated westwards into Eastern Europe in the 12th and 13th centuries when the Khazar Empire was collapsing.
Koestler used previous works by Douglas Morton Dunlop, Raphael Patai and Abraham Polak as sources. His stated intent was to make antisemitism disappear by disproving its racial basis.
Popular reviews of the book were mixed, academic critiques of its research were generally negative, and Koestler biographers David Cesarani and Michael Scammell panned it. In 2018, the New York Times described the book as "widely discredited."
Summary
Contents Koestler advances the thesis that Ashkenazi Jews are not descended from the historical Israelites of antiquity, but from Khazars, a Turkic people originating in and populating an empire north of and between the Black Sea and Caspian Sea. Koestler's hypothesis is that the Khazars – who converted to Judaism in the 8th century – migrated westwards into current Eastern Europe (primarily Ukraine, Poland, Belarus, Lithuania, Hungary and Germany) in the 12th and 13th centuries when the Khazar Empire was collapsing.
At the end of the book's last chapter, Koestler summarizes its content and his intentions as follows: "In Part One of this book I have attempted to trace the history of the Khazar Empire based on the scant existing sources. In Part Two, Chapters V-VII, I have compiled the historical evidence which indicates that the bulk of Eastern Jewry — and hence of world Jewry — is of Khazar-Turkish, rather than Semitic, origin. In the last chapter I have tried to show that the evidence from anthropology concurs with history in refuting the popular belief in a Jewish race descended from the biblical tribe."
Sources Mattias Gardell writes that Koestler's thesis is "partly based on amateur anthropology", and its scientific arguments come from The Myth of a Jewish Race (1975) by Raphael Patai and his daughter Jennifer.Biale, David. Blood and Belief: The Circulation of a Symbol Between Jews and Christians, University of California Press, 2008, , p. 259. It also relies on the work of earlier historians, particularly Russian-Israeli historian Abraham Poliak's Hebrew book Khazaria: Toledot mamlakhah yehudit (1951),Hundert, Gershon David. Jews in Poland-Lithuania in the Eighteenth Century: A Genealogy of Modernity, University of California Press, 2006, , p. 6 footnote 6. and the History of the Jewish Khazars (1954) by Douglas Morton Dunlop, the author whom Koestler himself describes as a main source. Neil McInnes writes that Dunlop was, however, "much more tentative" in his conclusions, as were other historians of Khazars, including Peter Golden and Moses Shulvass. Golden himself described the book as "controversial", stating it contained "sweeping claims of Khazar legacy and influence".Golden, Peter B., "Khazar Studies: Achievements and Perspectives", in Golden, Peter B.; Ben-Shammai, Haggai; Róna-Tas, András. The World of Khazars: New Perspectives, Brill Publishers, 2007, , p. 9.
Motive Koestler biographer Michael Scammell writes that Koestler told French biologist Pierre Debray-Ritzen he "was convinced that if he could prove that the bulk of Eastern European Jews (the ancestors of today's Ashkenazim) were descended from the Khazars, the racial basis for anti-Semitism would be removed and anti-Semitism itself could disappear".Scammell, Michael. Koestler: The Literary and Political Odyssey of a Twentieth-Century Skeptic, Random House, 2009, , p. 546. According to George Urban, Koestler's desire to connect Ashkenazi Jews with Khazars was "based on a tacit belief that the intellectual brilliance of and international influence of Hungarians and Jews, especially Hungarian Jews or Jewish-Hungarians, was due to some unexplained but clearly ancient affinity between the two peoples".Urban, George. Radio Free Europe and the Pursuit of Democracy, Yale University Press, 1997, , p. 200.
Reception In The Invention of the Jewish People, Shlomo Sand, historian of cinema, French intellectual history, and nationalism at Tel Aviv University, writes "while the Khazars scared off the Israeli historians, not one of whom has published a single paper on the subject, Koestler's Thirteenth Tribe annoyed and provoked angry responses. Hebrew readers had no access to the book itself for many years, learning about it only through the venomous denunciations".Sand, Shlomo. The Invention of the Jewish People, Verso Books, 2009, p. 238. Writing in The Wall Street Journal, Chronicle of Higher Education editor Evan Goldstein states "Sand suggests that those who attacked Koestler's book did so not because it lacked merit, but because the critics were cowards and ideologues. 'No one wants to go looking under stones when venomous scorpions might be lurking beneath them, waiting to attack the self-image of the existing ethnos and its territorial ambitions.'"Goldstein, Evan R. "Where Do Jews Come From?", The Wall Street Journal, 29 October 2009.
In the Arab world the theory espoused in Koestler's book was adopted by persons who argued that if Ashkenazi Jews are primarily Khazar and not Semitic in origin, they would have no historical claim to Israel, nor would they be the subject of the Biblical promise of Canaan to the Israelites, thus undermining the theological basis of both Jewish religious Zionists and Christian Zionists.See: Plaut, Steven. "The Khazar Myth and the New Anti-Semitism" , The Jewish Press, 9 May 2007. Rossman, Vadim. Russian Intellectual Antisemitism in the Post-Communist Era, University of Nebraska Press, 2002, , p. 86. The Saudi Arabian delegate to the United Nations argued that Koestler's theory "negated Israel's right to exist".Scammell, Michael. Koestler: The Literary and Political Odyssey of a Twentieth-Century Skeptic, Random House, 2009, , p. 547. Koestler did not see alleged Khazar ancestry as diminishing the claim of Jews to Israel, which he felt was based on the United Nations mandate and not on Biblical covenants or genetic inheritance.Barkun, Michael. Religion and the Racist Right: The Origins of the Christian Identity Movement, University of North Carolina Press, 1994, , pp. 144–145. In his view, "[t]he problem of the Khazar infusion a thousand years ago... is irrelevant to modern Israel."
Koestler's book was praised by the neo-Nazi magazine The Thunderbolt as "the political bombshell of the century", and it was enthusiastically supported by followers of the Christian Identity movement.Gardell, Mattias. Gods of the Blood: The Pagan Revival and White Separatism, Duke University Press, 2003, , p. 124. According to Jeffrey Kaplan, The Thirteenth Tribe was "Identity's primary source for the Khazar theory"; they felt Koestler's book confirmed their own beliefs regarding Jews, and sold it "through their mail order services". Goldstein writes that "Koestler and the Khazar theory he advanced lives on in the fever swamps of the white nationalist movement".Goldstein, Evan. "Inventing Israel", Tablet Magazine, 13 October 2009. Michael Barkun writes that Koestler was apparently "either unaware of or oblivious to the use anti-Semites had made of the Khazar theory since its introduction at the turn of the century."
Assessment After it was first published, Fitzroy Maclean in The New York Times Book Review called The Thirteenth Tribe excellent, writing "Mr. Koestler's book is as readable as it is thought-provoking. Nothing could be more stimulating than the skill, elegance and erudition with which he marshals his facts and develops his theories."Maclean, Fitzroy. "Shalom Yisrah", The New York Times Book Review, 29 August 1976, p. 219. Reviewing the work in the Washington Report on Middle East Affairs in 1991, journalist and author Grace Halsell described it as a "carefully researched book" that "refutes the idea of a Jewish 'race'."Halsell, Grace. "Book Reviews. The Thirteenth Tribe", Washington Report on Middle East Affairs, May/June 1991, p. 71.
Despite some positive reviews in the press, James A. Beverley writes "When The Thirteenth Tribe was released, the academic critique of its research was prompt, public, and generally negative",Beverley, James A. Nelson's Illustrated Guide to Religions, Thomas Nelson, 2009, , p. 342. and Evan Goldstein states that it was "savaged by critics". An August 1976 review in Time magazine described Koestler's theory as "all too facile, despite the obvious effort and time the author spent on his study", and stated that "Koestler offers a blizzard of information but not enough hard facts to support his thesis".Sheppard, R.Z. "Books: Caucasian Connection", Time magazine, 23 August 1976. A November 1976 review in National Review stated that the work had "neither the value of a well-executed honest piece of scholarship nor the emotional appeal of a polemic – only the earmarks of a poorly researched and hastily written book".Majeski, Jane. "Chutzpah: The Thirteenth Tribe, by Arthur Koestler", National Review 27, 12 November 1976, p. 1248, cited in Blumstock, Robert. "Going Home: Arthur Koestler's Thirteenth Tribe", Jewish Social Studies 48:2, 1986, p. 94. Koestler's analysis was described as a mixture of flawed etymologies and misinterpreted primary sources by Chimen Abramsky in 1976 and Hyam Maccoby in 1977.Abramsky, Chimen. "The Khazar Myth", Jewish Chronicle, 19, 9 April 1976.Maccoby, Hyam. "Koestler's Racism", Midstream, 23, March 1977.
Barkun describes the book as an "eccentric work", and writes that Koestler was "unequipped with the specialist background the subject might be thought to require", but that he "nevertheless made an amateur's serious attempt to investigate and support the theory." Professor of Polish-Jewish history Gershon D. Hundert wrote in 2006 "There is no evidence to support the theory that the ancestors of Polish Jewry were Jews who came from the Crimean Jewish kingdom of Khazaria", describing Koestler as the "best-known advocate" of the theory. In 2009, Jeffrey Goldberg wrote that the book was "a combination of discredited and forgotten [ideas]".
Koestler biographers have also been critical of the work. In Arthur Koestler: The Homeless Mind (1998), David Cesarani states it makes "selective use of facts for a grossly polemical end" and is "risible as scholarship". In Koestler: The Literary and Political Odyssey of a Twentieth-Century Skeptic (2009), Michael Scammell writes that Koestler's theory "was almost entirely hypothetical and based on the slenderest of circumstantial evidence", and takes the book as evidence that Koestler's brain "was starting to fail him".Scammell, Michael. Koestler: The Literary and Political Odyssey of a Twentieth-Century Skeptic, Random House, 2009, , p. 548.
Genetic research