Career
His lineage traced back to Ariq Böke who was a youngest brother of Möngke, Kublai and Hulagu. Arpa Ke'un came to power following the death of the Ilkhan Abu Sa'id in 1335. Almost immediately he had to deal with an invasion by Ozbek Khan of the Golden Horde.
He defeated the invasion, and furthermore used it as a pretext for executing Abu Sa'id's widow Bagdad Katun in an effort to cement his power. In 1336, he faced attack from the governor of Baghdad, Oirat 'Ali Padsah. The latter defeated him near Maraga on April 10, and soon after Arpa was captured and killed.
He was succeeded as Ilkhan by the puppet Musa.