Not much is known about the early origins of the Khazars, a semi-nomadic people who, in the late 6th century CE, established an empire covering the southeastern section of modern European Russia, southern Ukraine, Crimea and Kazakhstan. The kingdom of Khazaria long served as a buffer between the Christian Byzantine Empire and the Islamic Umayyad and Abbasid Caliphates. Sometime around the year 740 CE, the king and the ruling class, followed by members of the general population, decided to convert to Judaism.

Hasdai Learned of the Khazars

References to the Khazars adopting Judaism as their religion is found in Arabic, Christian and Jewish sources. However, the most famous account is found in the letters known as the Khazar Correspondence, exchanged between Rabbi Hasdai ibn Shaprut (c. 915–975), and Joseph, king of the Khazars. Hasdai (or Chasdai) ibn Shaprut was a fascinating individual in his own right.

Born in Jaen, Spain, Hasdai was a Jewish scholar and physician proficient in multiple languages. Originally appointed as physician to Caliph Abd-ar-Rahman III (912–961), he eventually became the caliph's faithful counselor. Although he didn’t bear the official title of vizier, he was effectively the minister of foreign affairs and arranged alliances with various foreign powers. He worked tirelessly for the betterment of his fellow Jews, and it is largely due to his efforts and support of Jewish learning that Spain became the new center of Torah learning after the Geonic period in Babylonia.

At first, Hasdai only heard scant rumors of the existence of a Jewish state. However, the existence of the Khazar state was eventually confirmed by two Jewish merchants, Mar Saul and Mar Joseph. Hasdai then decided to make contact with the Khazars.

Read: A Bio of Hasdai ibn Shaprut

The Khazars Accept Judaism

The initial attempt by Hasdai failed, since the Byzntines, who feared a direct alliance between Spain and the Khazars, held up Hasdai’s emissary on the pretext that the roads were not safe. But Hasdai persevered; he sent a new emissary and was eventually able to make contact.

In his return letter, King Joseph replied to Hasdai’s questions regarding the history of the Khazars and which tribe they were from.

King Joseph explained that his ancestor King Bulan decided to give up his pagan beliefs in order to accept one of the three leading faiths: Judaism, Christianity or Islam. King Bulan then arranged for representatives of each of the three faiths to participate in a debate in his presence:

On the third day he called all the sages together and said to them, "Speak and argue with one another and clarify which is the best religion." They began to dispute with one another without arriving at any results, until the king said to the Christian priest, "What do you think? Of the religion of the Jews and the Muslims, which is to be preferred?" The priest answered: "The religion of the Israelites is better than that of the Muslims."

The king then asked the imam: "What do you say? Is the religion of the Israelites or that of the Christians preferable?" The imam answered: "The religion of the Israelites is preferable."

Upon this, the king said: "If this is so, you both have admitted with your own mouths that the religion of the Israelites is better. Therefore trusting in the mercies of G‑d and the power of the Al-mighty, I choose the religion of Israel, that is, the religion of Abraham . . .”

King Joseph then described how, after King Bulan accepted Judaism, a descendant of his, King Obadiah, “reorganized the kingdom and established the Jewish religion properly and correctly. He built synagogues and yeshivot, brought in Jewish scholars, and rewarded them with gold and silver. [The Jewish scholars could have come from Baghdad and Constantinople.] They explained to him the Bible, Mishnah, Talmud and the order of divine services . . .”

Although the Khazar king, noblemen, and part of the population did indeed convert, it seems as though much of the population never embraced Judaism.

The Decline of the Khazars

Just a few years after Hasdai's correspondence with the Khazars, the Russian and Byzantine rulers combined forces to destroy the kingdom of the Khazars. They devastated their land, including their capital of Atil (c. 968–9). Although the Khazars continued to play an important role in that part of the world for another century, their fortunes eventually waned and they faded into oblivion.

Students in Spain

Rabbi Abraham ben David (Abraham ibn Daud, c. 1110–1180), in his Sefer Kabbalah (Book of Traditions), writes about the letter King Joseph sent to Hasdai ibn Shaprut informing him that he and his people followed the rabbinical faith. Rabbi Abraham ben David adds that even after the decline of the Khazars, some of their descendants came to Toledo, Spain, to learn Torah.

Evidence Amongst Viking Treasures

In 1999, a large Viking treasure was discovered on a farm in Sweden. Known as the Spillings Hoard, this treasure included Islamic, Nordic and Persian coins. One of the most noted coins in the hoard, dated to c. 800, is from the Khazar Kingdom and is referred to as the "Moses Coin." The coin is inscribed with the words "Moses is the messenger of G‑d" in contrast to the usual Muslim text "Muhammad is the messenger of G‑d."

The Kuzari by Rabbi Judah Halevi

The story of the Khazars would perhaps have been a footnote in Jewish history if not for Rabbi Judah Halevi (c. 1080–1141), who wrote a classic Jewish philosophical work commonly known as The Kuzari (or Al Khazari). The work's full title is “Book of Refutation and Proof on Behalf of the Despised Religion.”

Inspired by the story of the Khazars, The Kuzari takes the form of the debate (mentioned earlier) in which the king of the Khazars invites representatives of each of the three major religions to come and explain their beliefs. The group includes a Muslim imam, a Christian priest and a rabbi. After the king is won over by the rabbi's arguments, the rabbi demonstrates the superiority of his faith by bringing clear proof of the Giving of the Torah at Sinai and explaining the commandments in rational terms.

Instead of using complicated philosophical ideas, Rabbi Judah Halevi bases his arguments on history, tradition and common sense. In the introduction, the author states that the purpose of his work is to reply to the attacks of those who wish to denigrate Judaism. Thus the Kuzari has become one of the most important works of Jewish apologetics and has been reprinted many times and in many languages, including multiple English translations.

Read: A Bio of Rabbi Judah Halevi

(In the 18th century, Rabbi David Nieto [1654–1728] wrote Mateh Dan, also known as Kuzari Sheini [“Second Kuzari”], which is primarily aimed at proving the legitimacy of rabbinic tradition. It follows the conversational model of Judah Halevi’s Kuzari, picking up where he left off, with a series of dialogues defending rabbinic tradition against Karaitic arguments. This book has also been translated into English.)

Who Are the Descendants of the Khazars?

As mentioned, the final fate of the Khazars after their decline remains unknown. Nevertheless, this has not stopped some scholars from postulating that Ashkenazic Jewry is largely descended from Khazars, a theory that has been exploited for political and anti-Semitic purposes. However, this theory has no basis and has been debunked by historians, linguists and geneticists.

See: 16 Myths & Facts About Judaism & Jewish People