King of Sweden. Also a daughter by this marriage (Williamson, David. Debrett's kings and queens of Europe. Topsfield, Mass. : Salem House Publishers, c1988, pg. 121). Olof was his only son. He was of warlike disposition and conquered Finland, Esthonia and Livonia, earning the name of Eric the victorious. His wife Sigrid the Haughty was a proud beauty and eventually he could stand her no more. They separated after she had borne a son and a daughter. Eric and his brother Olof ruled reigned together in Uppsala. Olof died quite soon leaving Eric sole ruler. (Williamson, David. Debrett's kings and queens of Europe. Topsfield, Mass. : Salem House Publishers, c1988, pg. 121).