During the Viking Age, longships were the pinnacle of Scandinavian sea power. Their design evolved over many years, beginning in the Stone Age with the invention of the umiak(a type of open skin boat used by both Yupik and Inuit), and continuing up to the 9th century with the Nydam and Kvalsund ships. The longship appeared in its complete form between the 9th and 13th centuries.
They were often owned by coastal farmers and commissioned by the king in times of conflict, to keep a powerful naval force close at hand. Longships were used by the Norse in warfare, but they were troop transports and not warships. They were called dragonships by enemies such as the English because of their fierce dragon-shaped prows, which were used to frighten away sea monsters and evil spirits. When approaching land, the head could be removed to prevent scaring the friendly land spirits.