The Caribbean initially provided England's most important and lucrative colonies, but not before several attempts at colonisation failed. An attempt to establish a colony in Guiana in 1604 lasted only two years, and failed in its main objective to find gold deposits. Colonies in St Lucia (1605) and Grenada (1609) also rapidly folded, but settlements were successfully established in St. Kitts (1624), Barbados (1627) and Nevis (1628). The colonies soon adopted the system of sugar plantations successfully used by the Portuguese in Brazil, which depended on slave labour, and—at first—Dutch ships, to sell the slaves and buy the sugar. To ensure that the increasingly healthy profits of this trade remained in English hands, Parliament decreed in 1651 that only English ships would be able to ply their trade in English colonies. This led to hostilities with the United Dutch Provinces—a series of Anglo-Dutch Wars—which would eventually strengthen England's position in the Americas at the expense of the Dutch. In 1655, England annexed the island of Jamaica from the Spanish, and in 1666 succeeded in colonising the Bahamas.