Some European countries adopted slavery because of tradition. For instance, the Portuguese and Spanish enslaved Africans and Indians because their tradition allowed them to enslave people who were from a different race and religion. Slaves who became Christians were given freedom.

Furthermore, European colonists adopted slavery for economic reasons. For instance, English colonists used slaves for the production of sugar. A major factor that led to the adoption of slavery was the difficulty in finding labor due to disease outbreaks, which drastically reduced the population of the colonists. Moreover, Europeans who worked in farms demanded better working conditions. The high demand for labor resulted in the Atlantic slave trade becoming a profitable business. The slave trade became popular after colonists realized its economic impact. Slave traders would search for new markets and sell slaves for profit.