Gunnar was a Fremennik, a tribe of mountain people that today inhabit the Fremennik Province north of Kandarin. He was amongst those that believed the use of the newly-discovered runes defied the will of the Gods, and became the leader of a group of Fremenniks that attacked many magic-using settlements. The hardest stroke was seen in the near extinction of the Imcando Dwarves.
Gunnar led the Crusades from the Years 42 to 62 before being forced to abandon the invasion when his forces dwindled to near extermination. His people created Gunnarsgrunn on the border of Misthalin, where they planned to wait until they could launch a second attack. However, when the first Wizards' Tower was burned by Zamorakians in the Year 70, the art of runecrafting was lost. As a result, the Crusades never resumed. The current leader of the village Chieftain Gunthor, is his grandson, with Gudrun being his great granddaughter.