In 1315, Yury went to the Golden Horde and, after spending two years there, constructed an alliance with Uzbeg Khan. Upon Yury's marriage to the khan's sister Konchaka, Uzbeg Khan deposed Mikhail and nominated Yury as the Grand Duke of Vladimir. Back in Russia with a large force of Mongols, Yury approached Tver. However, Yuri's army was defeated and his brother Boris and his wife were taken prisoners. Thereupon he fled to Novgorod and sued for peace. At that time his wife, still held in Tver as a hostage, died unexpectedly. Yury availed himself of the confusion that followed and announced to the khan that she had been poisoned on Mikhail's order. The khan summoned both princes to Sarai and, after a trial, had Mikhail executed.