"The American Revolutionary War was fought mainly on land and won mainly on the water" Jack Coggins - Ships and Seamen of the American Revolution. In 1775, the Continental Navy numbered around 100 ships. In contrast, the British Navy had 270 ships and by 1783 had increased the number to 468. Despite this disparity, the Royal Navy suffered severely, largely through the actions of privateers, losing through sinking or capture nearly 200 ships. After 1778, when the British also had to face the fleets of France and Spain, American privateers multiplied. They inflicted severe damage on British ships and trade, costing Britain about 2,000 ships, GBP18 million, and 12,000 men captured. For the American Revolution to succeed, sea-borne trade with the rest of the world had to be maintained. Should this fail, then vital supplies of guns, the powder to fire them and not least men and ships to fight the British could not be relied upon. Mahan's masterly account of this neglected aspect of the wars brings to the fore the importance of the often ferocious engagements in the struggle for mastery of the sea, on the outcome of which hung the prospects of an Empire and the very course of history.