Mamai
Mamai (or Mamay) was a powerful military commander of Golden Horde in the 1370s, who resided in the western part of this nomadic state, which is now the Southern Ukrainian Steppes and the Crimean Peninsula. He split apart from Khans of the Golden Horde, trying to establish his own state.
Mamai, holding military rank of Commander of 10,000 troops (Division General) - "tumenbashy" ("temnik" in Russian), was not a member of the ruling Mongol dynasty (not one of Chingiz Khan's family). In 1378 - 1380 he tried to force Russians to pay annual tribute to him instead of the Golden Horde.
After being heavily defeated by Russians in 1380 Battle of Kulikovo, Mamai was assassinated in Kaffa (Crimea) by the Genoese, who could not forgive the total waste of a military unit of Genoese crossbow archers that were slaughtered by the Russians.
One of his sons later escaped to Lithuania, and, serving Grand Prince Vytautas the Great, received the title of Prince of Glina with multiple estates around the modern site of Poltava (Ukraine) in the early 1400s. At the very beginning of 16th century, this family (Slavicized and baptized by that time) moved on to Muscovite service. Eventually, in the 1520s, Princess Elena Glinskay became wife of Vasily III, Grand Prince of Moscow, and mother of Ivan the Terrible.
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