When Möngke died in 1259, Ariq Böke was elected Khan in the absence of his brothers, and had the support of most of the existing ministers and powerful families in the capital of Karakorum, such as Möngke's family, and other princes of the Golden family along with other forces in the capital of Karakorum including Torguud royal bodyguards and White Horde elites, as well as the Oirats, who were allied with him as one of the Oirat leaders was married to his daughter.
Cando Möngke morreu en 1259, Ariq Böke foi elixido Khan en ausencia dos seus irmáns, e tivo o apoio da maioría dos ministros e familias poderosas da capital de Karakorum, como a familia Möngke e outros príncipes da familia de Ouro xunto con outras forzas da capital de Karakorum, incluíndo as escoltas reais Torguud  e as elites da Horda Branca, así como os oirates, que eran aliedos del tan pois que un dos líderes oirate estaba casado coa súa filla.