This dissertation examines the links between the expansion of slavery, forced labor, racial ideology, and early Portuguese colonialism over the Ndombe and Quilengues populations of Catumbela, Dombe Grande, and Quilengues, three areas surrounding the port town of Benguela, Angola, from 1760 to 1860. From the expansion of the Atlantic slave trade during the late eighteenth and early nineteenth century to the period after its prohibition in 1836, the social and economic transformations experienced by these African communities intensified and laid the groundwork for further Portuguese colonization of Angola. In addition to slave trading operations, I demonstrate that the Portuguese colonial administration used the control over agricultural production and salt, chalk, and sulfur mining to advance divisions among local populations and exert their influence, often through legal regimes, over the regulation on ownership, free and enslaved labor, space, and knowledge. The success of local economic activities, the organization of chiefdoms, and the networks of trade attracted the interest of the Portuguese to establish colonial settlements and vassal relations with African communities. The Portuguese constant use of coercion, including the occupation of vassal territories and the imposition of local rulers, turned a system of indirect rule into direct colonialism.  Local people pushed for the recognition of their rights under colonial jurisdiction while protecting themselves from the violence of enslavement and Portuguese expansion. The importance of these areas for African populations made them stay or return and continue to engage in economic activities. They used colonial institutions to secure their possessions, have access to land, and trade. They fled and helped others flee from slave owners within these same areas, defying Portuguese authority and pushing for mechanisms to prevent the enslavement of free subjects. They also embraced labels for "Blackness" to claim a legitimate place as non-white individuals in the colonial society and jurisdiction. Overall, local people pushed to turn around the racial ideology that assumed the European moral superiority and thus excluded them from rights and belonging in their own communities. Ultimately, the making of Portuguese governance relied on constant negotiations between African rulers, free and enslaved subjects, and the colonial administration.