 The last Estonian county to hold out against the invaders was the island country of Saaremaa (Ösel), whose war fleets had continued to raid Denmark and Sweden during the years of fighting against the German crusaders.In 1206, a Danish army led by king Valdemar II and Andreas, the Bishop of Lund, landed on Saaremaa and attempted to establish a stronghold, without success.In 1216 the Livonian Brothers of the Sword and the bishop Theodorich joined forces and invaded Saaremaa over the frozen sea.