This is the monopoly granted by the government of Spain to sell captives and other people in its territories. According to the terms of the Treaty of Tordesillas, signed by Spain and Portugal in 1494, Portugal was granted a monopoly on trade and territorial claims in Africa.
Spain was granted a similar monopoly in the Americas, except for a small portion of eastern Brazil, which was placed in Portuguese hands. Thus, in the early 1500s, when Spain decided to import Africans to supplement and later replace Native American forced labourers in the Caribbean, Spain had to rely on outside suppliers. These suppliers worked under contract (in Spanish, asiento) with the Spanish government and purchased the exclusive right to supply a specified number of African slaves for a given period of time.
The first asiento on record was granted to a company from Genoa, Italy, in 1517. The company agreed to supply 1,000 captives between 1517 and 1525. In 1528 the asiento then passed to a company from the state of Brandenburg in eastern Germany. Subsequently, individual Spaniards and Portuguese held the contract. In 1701 the Guyana Company, chartered by the French government, received the asiento from Spain but lost it in 1713 to Britain as one of the provisions of the Treaty of Utrecht, which was formally ratified the following year. By that agreement Britain owned the right to sell captives for the next 30 years.
The Treaty of Utrecht resolved a series of disputes among the major European powers that had exploded into the War of the Spanish Succession (1701–1714). As a result of this treaty Britain became a major political force in Europe and a major trading power in the world of commerce. Britain dominated the slave trade until the British Parliament banned it in 1807.
