Tokhtamysh

Tokhtamysh, with the support of Timur, defeated the rebellious general Mamai and reunified the Golden Horde under his rule. He restored the Horde's authority over the Russian principalities, ending a period of fragmentation.

Tokhtamysh led a campaign against the Grand Duchy of Moscow. He besieged and captured Moscow, burning the city and massacring its inhabitants. The victory reasserted Mongol dominance over the Russian principalities.

Tokhtamysh invaded Timur's territory in Transoxiana, starting a war between the two Mongol rulers. Timur retaliated by invading the Golden Horde, defeating Tokhtamysh at the Battle of the Kondurcha River in 1391.

Timur decisively defeated Tokhtamysh at the Battle of the Terek River. The victory destroyed Tokhtamysh's army and led to the sack of Sarai, the capital of the Golden Horde. Tokhtamysh fled and never regained power.

After his defeat by Timur, Tokhtamysh fled to the Grand Duchy of Lithuania. He was killed in a skirmish with a rival Mongol faction near Tyumen. His death marked the end of the last attempt to reunite the Golden Horde.