<P> The Khan was married to Mary, illegitimate daughter of the Byzantine Emperor, securing the Byzantine - Mongol alliance after the defeat of Nogai . A report reached Western Europe that Toqta was highly favourable to the Christians . According to Muslim observers, however, Toqta remained an idol - worshiper (Buddhism and Tengerism) and showed favour to religious men of all faiths, though he preferred Muslims . </P> <P> During the late reign of Toqta, tensions between princes of Tver and Moscow became violent . Toqta might have considered eliminating the special status of the Grand principality of Vladimir, placing all the Rus' princes on the same level . Toqta decided to personally visit northern Russia, but he died while crossing the Volga in 1313 . </P> <P> After Uzbeg (Öz - Beg) assumed the throne in 1313, he adopted Islam as the state religion . He proscribed Buddhism and Shamanism among the Mongols in Russia, thus reversing the spread of the Yuan culture . By 1315, Uzbeg had successfully Islamicized the Horde, killing Jochid princes and Buddhist lamas who opposed his religious policy and succession of the throne . Uzbeg Khan continued the alliance with the Mamluks begun by Berke and his predecessors . He kept a friendly relationship with the Mamluk Sultan and his shadow Caliph in Cairo . After a long delay and much discussion, he married a princess of the blood to Al - Nasir Muhammad, Sultan of Egypt . </P> <P> The policy of Mongol rulers regarding the Rus' was to constantly switch alliances in an attempt to keep Russia and Eastern Europe weak and divided . With the assistance of Sarai, the Grand duke Mikhail Yaroslavich won the battle against the party in Novgorod in 1316 . While Michael was asserting his authority, his rival Yury of Moscow ingratiated himself into the favor of Uzbeg so that he appointed him chief of the Rus' princes and gave him his sister, Konchak, in marriage . After spending three years at Uzbeg's court, Yury returned with an army of Mongols and Mordvins . After he ravaged the villages of Tver, Yury was defeated by Mikhail in December 1318, and his new wife and the Mongol general, Kawgady, were captured . While she stayed in Tver, Konchak, who converted to Christianity and adopted the name Agatha, died . Mikhail's rivals suggested to Uzbeg Khan that he had poisoned the Khan's sister and revolted against his rule . Mikhail was summoned to Sarai and executed on November 22, 1318 . In 1322, Mikhail's son, Dmitry, seeking revenge for his father's murder, went to Sarai and persuaded the Khan that Yury had appropriated a large portion of the tribute due to the Horde . Yury was summoned to the Horde for a trial, but he was killed by Dmitry before any formal investigation . Eight months later, Dmitry was also executed by the Horde for his crime . </P>

How many miles did the khanate of the golden horde stretch from east to west