On 14 February, the festival of St Valentine, the chronicle records that Óláfr's forces launched an attack upon Rǫgnvaldr at Tynwald, where Rǫgnvaldr's troops were routed and he himself was slain. Tynwald may well have been the place where the Islesmen publicly inaugurated their kings, proclaimed new laws, and resolved disputes. As such, Óláfr's victory over Rǫgnvaldr at this site could have enhanced his royal status. Whilst Rǫgnvaldr's fall is laconically corroborated by the Icelandic annals, other sources appear to suggest that his death was due to treachery. The fourteenth-century "Chronicle of Lanercost", for example, states that Rǫgnvaldr "fell a victim to the arms of the wicked"; whilst the "Chronicle of Mann" states that, although Óláfr grieved at his half-brother's death, he never exacted vengeance upon his killers. Although the latter's account of Guðrøðr Dond's maiming and Rǫgnvaldr's death could be evidence that Óláfr was unable to control his supporters during these historical episodes, it is also possible that the compilers of this source sought to disassociate Óláfr from these acts of violence against his kin.