 In the 19th century, the descendants of the colonial Portuguese who had been so far been farm and plantation owners using Sena people and other African labor en masse shifted into slave trading, particularly to the South American colonies of Portugal.Initially they sold captured human beings as slaves, later they started selling African men and women from their own farms.Larger operations of "Prazos da Zambezia" included operating ships and slave voyages, and many ports and ships from Mozambique catered to this trade.