Ketil Thorkelsson, better known by his nickname Ketil Trout (in Old Norse, Ketill hængr) or Ketil Salmon was a Norwegian hersir of the late ninth century who settled in Iceland around 900 CE. He appears in Egils saga, the Landnámabók, and other Icelandic sources.
Ketil was the son of Thorkel of Namdalen, Jarl of Namdalen, and Hrafnhild, daughter of Ketil Trout of Hrafnista. Ketil was a man of great wealth and a close friend and kinsman of Thorolf Kveldulfsson and his brother Skallagrim.
When he heard that Harald I of Norway was launching an attack against Thorolf, Ketil was among the latter's allies who set out to support him. They arrived too late, and when the expedition arrived Thorolf had already been slain. In retaliation for Thorolf's death, Ketil gathered sixty warriors and raided Torgar, home of Harek and Hrærek (the sons of Hildirid), who had had slandered Thorolf to the king, and had contested the claim to Torgar with Thorolf. The Torgar estate had passed from Brynjolf (Ketil's non-blood related uncle), to Bard the White Brynjolfsson (Ketil's first cousin). Bard bequeathed the estate to Thorolf and gave no share to his half-brothers, the sons of Hildirid, whom he considered bastards. The sycophantic brothers were favorites of the king, and had prevaile on King Harald to confiscate Torgar from Tholf and give it to them. but the brothers did not cease maligning Thorolf's character.
In the raid the brothers were killed, and their property looted. Afterwards, Ketil loaded his allies, family and possessions onto two large longships and set sail for Iceland. They settled for the first winter on the eastern bank of the outer Rang River, but later moved eastwards and took land between "Thjors-river and Mark-fleet, from fell to firth, and made his home at Hof by east Rang-river".
With his wife Ingunn Ketil had several children, including Storolf, Herjolf, Helgi, Vestar, and Hrafn Hængsson, the last of whom was one of the first Lawspeakers.