The Golden Horde was a Mongol empire set up in 1251 with capital at Sarai on the River Volga. Its founder was Batu, grandson of Genghis Khan, and the Great Khan's commander in the conquest of Russia (which at that time lay wholly in Europe). The Republic of Novgorod, under Alexander Nevsky, remained free of Mongol rule.
They were named from their tents of cloth of gold. Another name for the state was the Kipchak Khanate.
It was at first subordinate to Genghis's successor, Ogotai or Ogodei Khan, but in 1260 it became fully independent, issuing its own coinage. These Mongol people became known to the Russians as the Tatars or Tartars, a name still used for their descendants in central Russia (Tatarstan).
In the early 1300s it converted to Islam, and in 1378 had united with the White Horde khanate of Central Asia. The resistance of the surviving Russian principalities, which retained some self-government under the khans, and from the 1390s the depredations of Timur, the conqueror of Persia, led to the weakening of the Golden Horde khanate, and it became subordinate to Timur during his lifetime.
In the 1400s it dissolved into three separate Tatar khanates: Crimea founded in 1430, Kazan in 1445, and Astrakhan in 1466. Moscow was retaken by Prince Ivan III in 1480, and first Muscovy then a united Russia became resurgent, conquering Kazan in 1552 and Astrakhan in 1556. Tatar Crimea (Crim Tartary) held out until 1783, the last remnant of the Empire of the Golden Horde.