Þangbrandr[1] was a missionary sent to Iceland by king of Norway Óláfr Tryggvason to convert the inhabitants to Christianity.
The Þangbrandr gave Óláfr the shield and, in return, the king promised to help and protect him in case he would need it.
[3] As a penance, Óláfr sent him to Iceland, where Þorvaldr Kodránsson and Stefnir Þórgilsson's missions had failed.
He travelled around the country and several other prominent Icelanders agreed to be baptized or at least to receive prima signatio.
The priest killed the skald Vetrliði Sumarliðason who had composed defamatory verses (níð) about him.
They explained that Þangbrandr had failed because he had proceeded with violence and murders[10] and they committed themselves to preaching Christian faith in Iceland.