Portuguese participation in the slave trade^129All the great powers of Europe then organized themselves to engage in
the slave trade. By the Treaty of Utrecht in 1713 the British obtained from the
Spanish crown the asiento contract for the Spanish West Indies, thus securing
the cream of the slave trade for themselves. The French came next, encouraged
by Colbert who, in setting out to develop the plantations in the French Antilles
and the French possessions in the Indian Ocean, gave a fillip to the slave trade.
In the face of this competition the Portuguese had lost their hegemony
on the West Coast, and the majority of their settlements there had fallen into
foreign hands. But Cape Verde remained a centre of the slave trade, for farming
was hard and unprofitable, and the colony, composed of half-castes, lived
mainly by slaving. In the course of the seventeenth century the increased demand
for slaves led to a resurgence of Portuguese activity north of the Equator: this
took the form of the building between 1677 and 1680 of the fortress of St John
the Baptist at Ajudá (Ouidah) in Dahomey, while a small factory was set up
in 1696 at Bissau. The population of Angola was decimated at about that time
by great smallpox epidemics, the most lethal being that which raged from 1685
to 1687. But this resurgence was incidental: Portugal's slave-trading activity
was really concentrated on Angola. Säo Tome was declining due to the competi-
tion of Brazilian sugar cane with its poorer-quality crop ; and the half-caste
population, in defiance of the central government in Lisbon (which had great
difficulty in imposing its authority), took up smuggling and slave-trading. Since
the Dutch occupation at Mpinda, Portuguese influence in the now disintegrated
Kingdom of Kongo was reduced almost to nil; and foreigners traded freely
on the coast of Loango, at Cabinda, at the mouth of the Congo, and on the
Angolan coast as far as Ambriz. The Portuguese several times tried to re-
establish themselves at Cabinda, even going to the lengths of starting to build
a harbour—which was destroyed by Admiral Marigny's fleet in 1783. The
authority of the Portuguese crown was really exerted only on the coast south
of the Dande as far as Benguela, and it was even so unable to check the smug-
gling that was rampant out of Luanda and Benguela.
The history of Angola up to the nineteenth century was entirely domi-
nated by the slave trade, for all attempts to encourage agriculture and mining
ended in failure. The climate, for one thing, was lethal ; of 2,000 soldiers sent
out between 1675 and 1694, only 300 survived; and, in contrast to farming,
slave-trading offered the appeal of a quick profit. Unlike what had happened
in Brazil, the Portuguese came up against organized populations who would not
let them through into the interior, where the climate was healthier. Native
brokers formed a screen between the coast and the hinterland so as to be able
to act as middlemen in the trade; consequently the only way inland was up
the rivers.
At the end of the seventeenth century the discovery of the gold mines of
Minas Gérais, in Brazil, led to an increased demand for slaves; and it was