Tolui

Tolui ( – 1232) was the youngest son of Genghis Khan and Börte. A prominent general during the early Mongol conquests, Tolui was a leading candidate to succeed his father after his death in 1227 and ultimately served as regent of the Mongol Empire until the accession of his brother Ögedei two years later. Tolui's wife was Sorghaghtani Beki; their sons included Möngke and Kublai, the fourth and fifth khans of the empire, and Hulagu, the founder of the Ilkhanate.

Tolui was less active than his elder brothers Jochi, Chagatai, and Ögedei during their father's rise to power, but once he reached adulthood he was considered the finest warrior of the four. He commanded armies under his father during the first invasion of Jin China (1211–1215), and his distinguished service during the Mongol invasion of the Khwarazmian Empire secured his reputation. After the fall of the cities of Transoxiana in 1220, Genghis dispatched Tolui early the following year to subjugate the region of Khorasan, which had begun to cause trouble for the Mongol armies. Tolui executed his orders with ruthless efficiency, assaulting the major cities of Merv, Nishapur, and Herat, and subjugating numerous others. Medieval chroniclers attributed more than three million deaths to the massacres he ordered at Nishapur and Merv; while these figures are considered exaggerated by modern historians, they are evidence of the abnormal brutality of Tolui's campaign.