unanimiter et constanter

Fêted on this day as the patron saint of Oslo, Hallvard Vebjørnsson (†1043) is venerated as a martyr for his violent death in defence of a pregnant slave woman (thrall or trell, see also).
The son and heir to a wealthy estate in Vikin in the south-eastern part of the kingdom near the capital region and relative of Saint Olaf, Hallvard believed in the professed innocence of the women in face of accusations of theft and attempted to ferry her to safety aboard his boat. The accusers killed them both with a volley of arrows, disposing of the woman on the shore they had sailed to, and realising that Hallvard’s absence would arouse suspicion, they tied a millstone around his neck to ensure the body could be sunk without a trace. Miraculous and inopportunely for the assailants, however, Hallvard’s corpse bobbed to the surface and revealed the men’s crimes. The contemporary coat of arms of the Norwegian capital portrays this iconography—this day also celebrated as Oslo-dagen, with the motto Unanimous and Constant.