Jon Ingesson Kuvlung (born 1157 - died 1188) was a pretender to the Royal Crown during the civil war era in Norway.
The leading man was Símon Kárason whose wife, Margrete Arnesdotter (Margrét Arnadóttir), had been the half-sister of King Inge I of Norway and the granddaughter of dowager Queen Ingrid Ragnvaldsdotter.
Margrét Arnadóttir was additionally the full sister of Nikolás Arnason, Bishop of Oslo and a prominent opponent of King Sverre.
Símon Kárason and Margrét Arnadóttir were also the parents of Philippus Simonsson, a future pretender to the throne of Norway.
The Church never spoke up against Jon for leaving his monastery, while his opponent King Sverre was heavily criticised for abandoning his prior duties as a priest on the Faroes.
The background for these conflicts were the unclear Norwegian succession laws, social conditions and the struggle between Church and King.