Kublai Khan the role of Emperor of China. By 1279, the Mongol conquest of the Song dynasty was completed and Kublai became the first non-Han emperor to conquer all of China. The imperial portrait of Kublai was part of an album of the portraits of Yuan emperors and empresses, now in the collection of the National Palace Museum in Taipei. White, the color of the royal costume of Kublai, was the imperial color of the Yuan Dynasty. Kublai Khan was the fourth son of Tolui, and his second son with Sorghaghtani Beki. As his grandfather Genghis Khan advised, Sorghaghtani chose a Buddhist
Mongol Empire his other sons, such as Tolui, Chagatai, or Jochi. The Toluids prevailed after a bloody purge of Ögedeid and Chagataid factions, but disputes continued among the descendants of Tolui. A key reason for the split was the dispute over whether the Mongol Empire would become a sedentary, cosmopolitan empire, or would stay true to their nomadic and steppe lifestyle. After Möngke Khan died (1259), rival kurultai councils simultaneously elected different successors, the brothers Ariq Böke and Kublai Khan, who fought each other in the Toluid Civil War (1260–1264) and also dealt with challenges from the descendants of other sons of