While still a youth, Vasily, who was the eldest son of Grand Prince Dmitry Donskoy (ruled Moscow 1359–89), travelled to the Tatar khan Tokhtamysh (1383) to obtain the Khan's patent for his father to rule the Russian lands as the grand prince of Vladimir. Diplomatically overcoming the challenge of the prince of Tver, who also sought the patent, Vasily succeeded in his mission. But he was subsequently kept at Tokhtamysh's court as a hostage until 1386 when, taking advantage of Tokhtamysh's conflict with his suzerain Timur Lenk (Tamerlane), he escaped and returned to Moscow.