The advent of the Wars of the Three Kingdoms in 1639 brought a halt to major migration, and a significant number of men returned to England to fight in the war. Massachusetts authorities were sympathetic to the Parliamentary cause and had generally positive relationships with the governments of the English Commonwealth and the Protectorate of Oliver Cromwell. The colony's economy began to diversify in the 1640s, as the fur trading, lumber, and fishing industries found markets in Europe and the West Indies, and the colony's shipbuilding industry developed. The growth of a generation of people born in the colony and the rise of a merchant class began to slowly change the political and cultural landscape of the colony, even though its governance continued to be dominated by relatively conservative Puritans.