By the mid-1600s, less than half a century after the English had opened the way for full-scale European settlement, serious crises were brewing in the American colonies. At first tensions were caused by a steadily increasing population: massive numbers of settlers required more land, additional dwellings and other accommodations, greater food supplies, and expanded trade and transportation networks. The immediate victims were Native Americans, who suffered mistreatment at the hands of colonists scrambling to grab land and natural resources. A demand for more laborers also created the institution of slavery, as millions of Africans were transported into the colonies during the seventeenth and eighteenth centuries. Among the colonists themselves, religious differences were escalating into confrontations, land squabbles were causing rebellions, and class divisions were breeding unrest.
