Sigtrygg Silkbeard

Sigtrygg II Silkbeard Olafsson was a Hiberno-Norse king of Dublin of the Uí Ímair dynasty. He was caught up in the abortive Leinster revolt of 999–1000, after which he was forced to submit to the King of Munster, Brian Boru. His family also conducted a double marriage alliance with Boru, although he later realigned himself with the main leaders of the Leinster revolt of 1012–1014. He has a prominent role in the 12th-century Irish Cogadh Gaedhil re Gallaibh and the 13th century Icelandic Njal's Saga, as the main Norse leader at the Battle of Clontarf in 1014.