To the northwest of the Arab Caliphate and to the northeast of the Byzantine Empire laid the Khazar Khaganate. It broke away from the crumbling Göktürk Khaganate in 650 CE amidst wars with the Tang dynasty of China. Khazaria had a system of dual kingship. A higher king, shown reverence by all, was chosen from a house of notables. Historians believe this may have been a princely line of Chinese. The lower king performed the administrative duties and governed. The lower king would prostrate elaborately when in the presence of the higher. This was probably a way of balancing the sensibilities of different peoples.
The Khazars were not a single ethnic or religious group, like Arabs or Jews. Historians estimate there were between 25 and 28 distinct ethnic populations as well as the ruling elite living in Pax Khazaria, including many Slavic groups. Khazaria was a buffer between the Christian West and Muslim East, but more than that, it was a trade route between them. Import and export taxes, and partaking in the Muslim slave trade by supplying Slavic slaves, became major sources of Khazars revenue. This was used to maintain an unusual for the era standing army to defend the borders from raiders.
Everyone in those days knew that the best trade merchants were the Radhanites. These Jewish merchants were highly respected, multilingual, and well known for having established four reliable trade routes between France and China early in the ninth century, one through the capital of Khazaria. Some theories propose Radhanite influence led to the Khazar kings’ conversions to Judaism. The Rhadanites specialized in small, light goods such as cloths and spices, dominating the spice trade for a century, but also sold Slavic people to Muslims as slaves as the Khazars did.
Jewish Radhanites were considered neutral third parties in the religious tensions between Christians and Muslims, and these merchants had an honest reputation that allowed them to continue trading with everyone at points when no one was willing to trade with anyone else. To protect themselves from nomadic caravan raiders stealing their silver, the Radhanites invented a system of “letters of credit”. This was a more advanced form of banking than simple money lending, which allowed them to buy and sell goods at each port without carrying coin. They probably brought the Chinese art of paper making to Europe.
Khazaria had years of prosperity but by the late 800s, the map was getting uncomfortably squeezed. Everyone was raiding, invading, and going to war with the Khazars for their control of the Volga River and coasts on the Caspian and Black Seas. The Khazar Khaganate fell in 969 to Rus Kiev (Russian) forces, and Khazars fade from history by 1106. There is an antisemitic conspiracy theory that Ashkenazi Jews are descended from Khazars and not from Israelites; that they therefore have no connection to the Holy Land, and Zionism is thus an illegitimate cause. Neither history nor genealogy nor genetic testing confirm this baseless accusation, meant to deny Jewish people the right to a homeland.