Slavery began in the American colonies in the early 1500s as the Portuguese began exploring Africa and trading slaves. By the 1700s, the growth of industries like rice, tobacco and cotton created a large demand for slave labor in the Southern colonies. To maintain control over the growing slave population, colonies implemented strict slave codes that severely limited the rights of slaves. Throughout this period, slaves resisted their condition through acts like slow work, escape and occasional rebellions, the largest being the Stono Rebellion in 1739. Slavery would not be abolished in the United States until 1865 with the end of the Civil War.