How did liberalism of the early 1800s reflect enlightenment ideas?

The origins of slavery can be traced back much further than the eighteenth- and nineteenth-century plantations in the southern United States. By the time the English had begun to settle permanent colonies in North America, the Spanish and Portuguese had developed a model of slavery to provide labor for commercial agriculture. This model was critical for the development of slavery in Anglo-America.
Slavery had existed in Africa prior to the arrival of Europeans, although it did not take the form it would assume in the Western Hemisphere. There, it would become integrally connected to commercial agriculture and result in defining the slave as chattel, or personal property. In the African system, slavery was not generational; a child did not become a slave to his mother's owner. Furthermore, under the African system, slaves were not defined as property and they could rise to positions of influence. Under this system, slavery was not racially prescribed.