Knut Alvsonn, of the Swedish "Tre Rosor" noble family, was the great-grandson of Sigurd Jonson's sister He was a Royal Councillor of Norway, and holder of vast landed properties around Norway, having inherited such from his Giske-Bjarkoy-Sudreim ancestors. Knut Alvsonn was a personal enemy of Lord Henrich Krummedige, Danish royal governor in Norway. That made him somewhat an opponent of the union; and he was an ally of Sweden's anti-unionist Regent Sten Sture the Elder. Knut Alvsonn is said to have built a basis to grab the Norwegian throne, starting in the late 15th century. He started an open rebellion against King John of Denmark, took some Norwegian castles, but was killed in 1502 by King Johns' minions.