The foreign lands with which these companies traded furnished at the beginning of this period the only places to which goods could be exported and from which goods could be brought; but very soon that series of settlements of English colonists was begun, one of the principal inducements for which was that they would furnish an outlet for English goods. The "Plantation of Ulster," or introduction of English and Scotch settlers into the north of Ireland between 1610 and 1620, was the beginning of a long process of immigration into that country. But far the most important plantations as an outlet for trade as in every respect were those made on the coast of North America and in the West Indies. The Virginia and the Plymouth Companies played a part in the early settlement of these colonies, but they were soon superseded by the crown, single proprietaries, or the settlers themselves. Virginia, New England, Maryland, the Carolinas, and ultimately New York, Pennsylvania, and Georgia on the mainland; the islands of Bermudas, Barbadoes, and Jamaica, and ultimately Canada, came to be populous colonies inhabited by Englishmen and demanding an ever increasing supply of English manufactured goods. These colonies were controlled by the English government largely for their commercial and other forms of economic value. The production of goods needed in England but not produced there, such as sugar, tobacco, tar, and lumber, was encouraged, but the manufacture of such goods as could be exported from England was prohibited. The purchase of slaves in Africa and their exportation to the West Indies was encouraged, partly because they were paid for in Africa by English manufactured goods, partly because their use in the colonies made the supply of sugar and some other products plentiful and cheap. Closely connected with commerce and colonies as a means of disposing of England's manufactured goods and of obtaining those things which were needed from abroad was commerce for its own sake, for the profits which it brought to those engaged in it, and for the indirect value to the nation of having a large mercantile navy.