Between 1700 and 1770, the population of the southern colonies of Virginia, Maryland, North Carolina, South Carolina, and Georgia grew almost ninefold. By 1770, about twice as many people lived in the South as in either the middle colonies or New England. As elsewhere, natural increase and immigration accounted for the rapid population growth. Many Scots-Irish and German immigrants funneled from the middle colonies into the southern backcountry. Other immigrants were indentured servants (mostly English and Scots-Irish). But slaves made the most striking contribution to the booming southern colonies, transforming the racial composition of the population. Slavery became the defining characteristic of the southern colonies during the eighteenth century, shaping the region’s economy, society, and politics.