Navigation Acts, the name given to laws regulating trade and commerce between Great Britain, its colonies, and other parts of the world. The first act, passed in 1651, stipulated that no merchandise was to be carried to England or its colonies except by English ships built and manned by English subjects. In 1660 another act forbade certain raw materials, such as sugar and tobacco, from being shipped from English colonies to anywhere but England or other colonies. Later acts forbade direct trade between continental Europe and the colonies, and forbade most manufactured goods from being sent to England from the colonies. After the union of 1707 these laws also applied to Scotland.
The Navigation Acts were intended to make the colonies a supplier of raw materials and a consumer of manufactured goods of the mother country, in accordance with mercantilist doctrine. They also encouraged development of the British merchant marine. The acts probably aided the growth of the British Empire for a time, but they were increasingly resented by American colonists in the 18th century, and are usually considered one of the causes of the American Revolution. During the early 19th century many of the acts were modified, and they were repealed in the 1840's.