Ariq Böke (1219–1266), the components of his name also spelled Arigh, Arik, Bukha, Buka (Mongolian: Аригбөх; Chinese: 阿里不哥), was the youngest son of Tolui (1192–1232), a son of Genghis Khan. After the death of his brother the Great Khan Mongke, Ariq Boke briefly took power while his brothers Kublai (more commonly known as Kublai Khan) and Hulegu (or Hulagu) were absent. When Kublai returned for an election in 1260, rival factions could not agree, and elected simultaneous claimants Kublai and Ariq Boke to the throne, resulting in a war for succession which marked the beginning of civil war in the Mongol Empire. Ariq Boke was supported by the traditionalists of the Mongol Empire, while his brother Kublai Khan was supported by the senior princes of North China and Manchuria.

Ariq Boke was the youngest son of Sorghaghtani Beki and Tolui, the youngest son of Genghis Khan. When Genghis died in 1227, the leadership of the Empire passed to Genghis' son (Ariq Boke's uncle), Ogedei. He peacefully attended the elections of both his uncle Great Khan Ogedei and Ogedei's successor Guyuk. After his eldest brother Mongke was enthroned in 1250, his family became even more powerful among the Chingisids. Ariq Böke is also known for being sympathetic towards Christianity; this is known from the account of Franciscan William of Rubruck, who was an envoy of French King Louis IX.