The next serious threat came in 1193 with the Øyskjeggene (the Isle Beards). This group's pretender to the throne was Sigurd, a child claimed to be the bastard son of Magnus Erlingsson. The real leader was Hallkjell Jonsson who was Magnus’ brother-in-law. Conspiring with the Earl of Orkney, Harald Maddadsson, Hallkjell gathered most of his men on the Orkney and Shetland Islands, hence the name of the group. After establishing themselves in Viken, the Øyskjeggene sailed on to Bergen. Although they occupied the city itself and the surrounding regions, a force of Birkebeiners held on in Sverresborg castle. In spring 1194 Sverre sailed south to confront the Øyskjeggene. The two fleets met 3 April in the Battle of Florvåg ("slaget ved Florvåg"). Here the battle experience of the Birkebeiner veterans proved to be decisive. Hallkjell fell with most of his men.