In 1252, Alexander Nevsky met with Sartaq at Sarai. Alexander received yarlyk (license) to become Grand Duke of Vladimir in vassalage to the Mongol Khanate. According to Lev Gumilev he became Sartaq's anda (sworn brother, akin to blood brother) and an adopted son of Batu Khan.[4]
His reign as khan of the Golden Horde was short-lived. He died in 1256 before returning from Great KhanMöngke's court in Mongolia, less than one year after his father, probably having been poisoned by his uncles Berke and Berkhchir. Sartaq was succeeded by Ulaqchi briefly in 1257, before his uncle Berke succeeded to the throne. It is not clear whether Ulaqchi was his brother or his son.
^"Early in 1253 a report reached Acre that one of the Mongol princes, Sartaq, son of Batu, had been converted to Christianity", Runciman, p. 280. See Alexander Nevsky for details.
^"Sartach examined the bible, and the cross with the image on it, putting some questions respecting both ; but our traveller was dismayed to hear nothing that favoured the report, upon which this painful journey had been undertaken, of his being a believer in the gospel. He never even seemed to refer to the subject, except in a tone of scoffing and derision. On inquiry, the sole ground of the rumour was found to be, that when christian merchants, many of whom passed this way, brought liberal presents, they were graciously accepted ; but when Mohammedans offered larger gifts, they met a welcome still more cordial." Travels of Marco Polo, by Hugh Murray, p. 70.
^Rashid al-Din - Universal History, see: Tale of Jochids
