The Navigation Acts were a series of laws passed by the British Parliament before the American Revolution. These laws demanded that American goods be shipped on British boats staffed by British sailors, and could only be sold in Britain. Also, colonists could only buy goods from Britain. This prevented the Americans from enjoying a competitive worldwide market, as they could not buy cheaper French goods, or sell to Spain, who might pay a higher price. Anger over British tyranny (which included numerous other acts, as well as the Boston Massacre) led to the American Revolution.