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 Israelit

Shlomo Sand is an Israeli post-Zionist historian and socialist. He has served as an emeritus Professor of History at Tel Aviv University since 2014. He is known for his book The Invention of the Jewis