Throughout the eighteenth century European powers with overseas colonies and interests in trade were in frequent conflict. For much of the time the Caribbean was the focal point of these clashes, and it is with the problems of administering a navy there, during the first war waged on a large scale, that this book is concerned.

The outbreak of war in 1739 was the culmination of the efforts by Britain to break into Spain's colonial trade, which had been pursued since the Treaty of Utrecht had brought the War of Spanish Succession to a close in 1713. This had given Britain a toehold in the Asiento, an agreement that allowed her to supply the Spanish colonies with slaves for the next thirty years. In addition, she was allowed to send one ship a year to trade at the annual fair at Porto Bello. These rights were entrusted to the South Sea Company, whose factors took up residence in the ports of the Spanish colonies. The opportunity thus offered for private trading was not missed, and ships that came from the British West Indies, ostensibly to supply the factors, rarely failed to have trading goodson board. Similarly, the Porto Bello ship broke the terms of the agreement by reloading under cover of darkness from lighters bringing necessaries. But the abuses of the legal trade were only one cause of the friction. Most of the trouble arose from the smuggling carried on between the British Caribbean islands and the smaller ports of Spanish America. By avoiding the payment of taxes and import dues, the smugglers were able to undercut the prices of legal imports.