The prazeros arose from Portuguese expansion in the late 15th century. Operating from the mercantile principle that wealth equals power, the Portuguese concentrated on a search for precious metals, especially gold and silver. After Vasco da Gama sailed from Portugal to India in 1498, Portugal sought to gain control of the gold trade in East Africa.
Before this time the Swahili city-states located between what is now Somalia and Mozambique had acted as intermediaries for the output of the gold mines of the Shona empire of Monomutapa, which is located in what is now eastern Zimbabwe and western Mozambique.
Portugal seized the Swahili city-states between 1506 and 1512 and, although the northern city-states slipped out of their control between 1648 and 1729, maintained control of the southern city-states, especially Sofala.
By the mid-17th century Portugal, a relatively small country of perhaps 1 million, decided to maintain some degree of control through the prazero system in its African territories. Concentrated in Mozambique, the hinterland of Sofala and the site of some of the goldfields, the prazero system was to last until approximately 1940 and, in part, reflected the lack of firm Portuguese control in its overseas African colonies.
The prazeros, holders of leases from the Portuguese Crown, were similar to the holders of the latifundia in Latin America but held a larger number. In practice, they were basically independent from 1650 to 1900.
Nominally required to defend Portuguese interests, they also derived rights from the loosely organized Shona states of Monomutapa and its successors. By 1700 they were functioning as local African leaders. They had taken African wives, although they continued to emphasize their Portuguese roots by sending their wives and children to Portuguese schools.
By 1800 the prazeros were more or less African-Portuguese and were actively engaged in the local slave trade. At the height of slave trading in Mozambique, the prazeros dominated trade and were involved in the export of perhaps 15,000 slaves per year.
The beginning of the end of the prazeros as a privileged class arose from two factors between 1850 and 1890, the abolition of slavery and the scramble for Africa, which endangered Portugal’s position in Africa.
The latter directly affected the economic base when Great Britain, in order to forestall the German attempt to connect German Southwest Africa (now Namibia) and German East Africa (now Tanzania), occupied the major goldfields of the Shona states.
The final end of prazero power came between 1880 and 1914 when Portugal sought to reassert control in its attempt to preempt British and German ambitions. Europeans were anxious to use African labor, materials, and markets for their increasing factory production.
When the Portuguese embarked upon the reassertion of their authority in the Zambezi Valley, they utilized three chartered companies, particularly the British-controlled Zambezia Company, which controlled labor and markets and expanded Portuguese control indirectly by, along with the other companies, establishing military posts and building roads, ports, and the transterritorial railroad.
Labor was mobilized to work on the newly developed plantations, especially in cotton and sugar, which were exported through the port of Beira. In the process most holdings of the prazero class were absorbed by the companies. By 1940 the prazeros had virtually disappeared as a dominant class.