The following is a list of Khazar rulers. Early Khazar rulers Khazar Khagans (Ashina dynasty) The Khagans were supreme chiefs of the people, holding positions of much influence and spiritual authority, but with little day-to-day command. Khazar Beks The Khagan Beks were war chiefs, military commanders who exercised considerable day-to-day authority, and were sometimes regarded by outsiders as the supreme lords of the Khazar nation. Conversion to Judaism Hazer Tarkhan's army was annihilated at Itil in 737 AD, and the Umayyad Caliphate imposed Islam upon the Khazars. Nevertheless, the Caliphs could not adequately garrison Khazaria, and within a few years the Khazars were once again independent. The famous conversion to Judaism seems to have occurred about this time. The date of the actual conversion to Judaism is a matter of some controversy. According to Yehuda Halevi in Kuzari, it occurred around 740 AD, though some Arab sources point to a date closer to the end of the 8th century or early 9th century, and more recent scholars have postulated that 861 AD, the date of St. Cyril's visit to Khazaria, was the year of the conversion to Judaism. The 2002 discovery of a coin hoard in Sweden further complicates the issue, as some of the coins bear dates from the early 9th century and the legends "Ard al-Khazar" (Land of the Khazars) and "Moses is the Prophet of God". Since the coins date from 837 AD or 838 AD, some scholars think the conversion occurred in 838 AD. Bulan Sabriel was the Khazar ruler at the time of the conversion, but in the list below all the dates up to Aaron I are based on a presumed 740 AD conversion date. Bulanid dynasty Late Khazar Rulers In 969 AD, Sviatoslav I of Kiev sacked Itil, the capital of the Khazar Khaganate. Khazar successor states appear to have survived in the Caucasus and around the Black Sea. We know of two later Khazar rulers: Collapse of Khazar power Georgius Tzul was captured by a joint Rus'-Byzantine expedition and his state was destroyed. Shortly thereafter, the Kipchaks became masters of the Pontic steppe (see Cumans). However, there continue to be tantalizing references, in Muslim sources, of battles against "Khazars" in the Caucasus well into the late 11th century. Whether Khazar states continued to survive or their name was used generically to describe Caucasian highlanders is unclear. The fate of the Jewish Khazars