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The Thirteenth Tribe: The Khazar Empire and Its Heritage (1976) by Arthur Koestler
In this book Arthur Koestler traces the history of the ancient Khazar people, who from around 750 AD, converted to Judaism. They lived in the Caucasian region, modern-day Ukraine, and were related to other Turkish tribes, the Magyars, Huns, and Oghuz. Were they wiped out in the Middle Ages by the Mongol hordes of Gengis Khan sweeping westward at around 1222 AD? There is substantial evidence that the survivors migrated north and west, primarily to Hungary and Poland.
Their influence on European history was considerably greater than their numbers might suggest, as they formed a buffer state between the expanding Islamic empire and Byzantium, and later slowed the southward marauding Viking Rus, who eventually served as the mercenary Varangian Guard in Constantinople. Thus the Khazars, by rejecting Orthodox Christianity and Islam, choosing instead Judaism, did so primarily for political purposes. The reasoning went that the commonality of the Hebrew Scripture’s acceptability to Jews, Christians and Muslims alike aided diplomacy and commercial interests.
David Keys, in Catastrophe: An Investigation into the Origins of the Modern World cites the Khazars and their migration as evidence of the widespread displacement of peoples after 536 AD, and an explanation of the relatively sudden appearance of the Northern European Jewish (Yiddish speaking) communities.
What implications are there of this theory, in linking the origin of the Northern European Jews, the Ashkenazim, with the migrating Khazars? Zionism was the political Jewish movement that sought a Jewish homeland in Palestine. The United Nations in 1947 partitioned Palestine into an Arab and a Jewish state. Without commenting on the complex political situation in the modern day Middle East, no state anywhere in the world today depends for its existence on a genetically pure link with a historical `mother-race’. Ironically, such a concept we normally might associate with Nazism.
Koestler sums up his argument by claiming the philosophical, artistic and scientific achievements of individual Jews consist of contributions to the culture of their host nations; they do not represent a common cultural inheritance, or autonomous body of traditions. At first, this seemed at odds with the spirit of the major Jewish writers of the twentieth century. Koestler argues that the Jews of the Diaspora, at least in the present day, have little in common except a religion the majority do not practice or believe in, and the shared trauma of the Holocaust, the effect of which may lessen in the future. The national identity of Israel then, does not depend on the European heritage that originated in Khazaria.