The British Admiralty’s decision against the American trade ship Essex in 1805 is an example of British policy toward American trade during the Napoleonic wars. Essex, being a merchant ship of the neutral United States, picked up cargo at Cadiz, Spain, with the ultimate destination of Havana, Cuba, a Spanish colony. Carrying cargo between ports of this French ally made the ship liable for seizure, but to give the appearance of neutral trade, the master of the Essex landed the cargo at Salem, Massachusetts and then re-shipped it for Havana. Though this practice had been tolerated for many years, attitudes changed when warfare recommenced between the British and French empires in 1803. Trading ships of neutral nations were seized by both sides, but since the stronger British Navy had control of the oceans and the United States was the leading re-exporter of goods, the issue affected these two nations the most.
By the end of 1807, the governments of both Great Britain and France had issued orders forbidding any trade with the other or their allies. In effect, it made any merchant ship fair game. President Thomas Jefferson ordered a national embargo of all foreign trade, and its enforcement damaged the domestic economy and sparked a lively system of evasion. Before Jefferson left office in 1809, the law had been changed to forbid trade with Great Britain, France, or their allies.