In 1469 Shetland came under nominal Scottish control, although the Norse 'Lairds of Norway' kept their Papa Stour estates until the 17th century. In the 16th century merchants from Bremen and Hamburg were operating a summer trading booth to buy fish from the local fleet. By the 18th century, two Scottish lairds, Thomas Gifford of Busta, and Arthur Nicolson of Lerwick, owned the island. They maintained a prosperous Haaf (Old Norse: 'deep sea') fishing industry, undertaken in the summer months using six-oared boats known as sixareens.