Sturla was more aggressive : he sent his uncle back to Norway , and started warring on the chieftains who refused to accept the king 's demands .
In 1235 , Snorri 's nephew Sturla Sighvatsson also accepted vassalage under the king .
Sturla Sighvatsson was more aggressive : nephew sent nephew 's uncle back to Norway , and started warring on the chieftains who refused to accept the king 's demands .
In 1235 , Snorri 's nephew Sturla Sighvatsson also accepted vassalage under the king .