force. The Scottish naval forces were defeated by Oliver Cromwell's navy and when Scotland became part of the Commonwealth in 1653, they were absorbed into the Commonwealth navy. After the Restoration Scottish seamen received protection against arbitrary impressment, but a fixed quota of conscripts for the English Royal Navy was levied from the sea-coast burghs. Royal Navy patrols started to extend their routes into Scottish waters, and in the Second (1665–1667) and Third Anglo-Dutch Wars (1672–1674), between 80 and 120 captains took Scottish letters of marque and privateers played a major part in the naval conflicts. In the 1690s, a small fleet of five ships was established by merchants for the Darien scheme, and a professional navy of three warships was established to protect local shipping in 1696. After the Act of Union in 1707, these vessels and their crews were transferred to the British Royal Navy. Origins By the late Middle Ages the kingdom of Scotland participated in two related maritime traditions. In the West was the tradition of galley warfare that had its origins in the Viking thalassocracies (sea-based lordships) of the Highlands and Islands and which stretched back before that to the sea power of Dál Riata that had spanned the Irish Sea. In the east it participated in the common northern European sail-driven naval tradition. The key to the Viking success was the long-ship, a long, narrow, light, wooden boat with a shallow draft hull designed for speed. This shallow draft allowed navigation in waters only deep and permitted beach landings, while its light weight enabled it to be carried over portages. Longships were also double-ended, the symmetrical bow and stern allowing the ship to reverse direction quickly without having to turn around. The longship was gradually succeeded by (in ascending order of size) the birlinn, highland galley and lymphad, which, were clinker-built ships, usually with a centrally-stepped mast, but also with oars that allowed them to be rowed. Like the longship, they had a high stem and stern, and were still small and light enough to be dragged across portages, but they replaced the steering-board with a stern-rudder from the late twelfth century. The major naval power in the Highlands and Islands were the MacDonald Lord of the Isles, who acted as largely independent kings and could raise large fleets for use even against their nominal overlord the King of Scots. They succeeded in playing