The Portuguese established themselves on the west coast of Africa towards the close of the 15th century. The river Congo was discovered by Diogo Cam or Cao in 1482. He erected a stone pillar at the mouth of the river, which accordingly took the title of Rio de Padrao, and established friendly relations with the natives, who reported that the country was subject to a great monarch, Mwani Congo or lord of Congo, resident at Bonza Congo. The Portuguese were not long in making themselves influential in the country. Gonçalo de Sousa was despatched on a formal embassy in 1490; and the first missionaries entered the country in his train. The king was soon afterwards baptized and Christianity was nominally established as the national religion. In 1534 a cathedral was founded at Bonza Congo (renamed Sao Salvador), and in 1560 the Jesuits arrived with Paulo Diaz de Novaes. Of the prosperity of the country the Portuguese have left the most glowing and indeed incredible accounts. It was, however, about this time ravaged by cannibal invaders (Bangala) from the interior, and Portuguese influence gradually declined.
The attention of the Portuguese was, moreover, now turned more particularly to the southern districts of Angola. In 1627 the bishop's seat was removed to Sao Paulo de Loanda and Sao Salvador declined in importance. In the 18th century, in spite of hindrances from Holland and France, steps were taken towards re-establishing Portuguese authority in the northern regions; in 1758 a settlement was formed at Encoje; from 1784 to 1789 the Portuguese carried on a war against the natives of Mussolo (the district immediately south of Ambriz); in 1791 they built a fort at Quincollo on the Loje, and for a time they worked the mines of Bembe. Until, however, the "scramble for Africa" began in 1884, they possessed no fort or settlement on the coast to the north of Ambriz, which was first occupied in 1855. At Sao Salvador, however, the Portuguese continued to exercise influence. The last of the native princes who had real authority was a potentate known as Dom Pedro V. He was placed on the throne in 1855 with the help of a Portuguese force, and reigned over thirty years.
In 1888 a Portuguese resident was stationed at Salvador, and the kings of Congo became pensioners of the government.
Angola proper, and the whole coast-line of what now constitutes the province of that name, was discovered by Diogo Cam during 1482 and the three following years. The first governor sent to Angola was Paulo Diaz, a grandson of Bartholomew Diaz, who reduced to submission the region south of the Kwanza nearly as far as Benguella. The city of Loanda was founded in 1576, Benguella in 1617. From that date the sovereignty of Portugal over the coast-line, from its present southern limit as far north as Ambriz (7° 50' S.) has been undisputed save between 1640 and 1648, during which time the Dutch attempted to expel the Portuguese and held possession of the ports. Whilst the economic development of the country was not entirely neglected and many useful food products were introduced, the prosperity of the province was very largely dependent on the slave trade with Brazil, which was not legally abolished until 1830 and in fact continued for many years subsequently.
In 1884 Great Britain, which up to that time had steadily refused to acknowledge that Portugal possessed territorial rights north of Ambriz, concluded a treaty recognizing Portuguese sovereignty over both banks of the lower Congo; but the treaty, meeting with opposition in England and Germany, was not ratified. Agreements concluded with the Congo Free State, Germany and France in 1885-1886 (modified in details by subsequent arrangements) fixed the limits of the province, except in the S.E., where the frontier between Barotseland (N.W. Rhodesia) and Angola was determined by an Anglo-Portuguese agreement of 1891 and the arbitration award of the king of Italy in 1905 (see AFRICA: History). Up to the end of the 19th century the hold of Portugal over the interior of the province was slight, though its influence extended to the Congo and Zambezi basins. The abolition of the external slave trade proved very injurious to the trade of the seaports, but from 1860 onward the agricultural resources of the country were developed with increasing energy, a work in which Brazilian merchants took the lead. After the definite partition of Africa among the European powers, Portugal applied herself with some seriousness to exploit Angola and her other African possessions.
Nevertheless, in comparison with its natural wealth the development of the country has been slow. Slavery and the slave trade continued to flourish in the interior in the early years of the 20th century, despite the prohibitions of the Portuguese government. The extension of authority over the inland tribes proceeded very slowly and was not accomplished without occasional reverses. Thus in September 1904 a Portuguese column lost over 300 men killed, including 114 Europeans, in an encounter with the Kunahamas on the Kunene, not far from the German frontier. The Kunahamas are a wild, raiding tribe and were probably largely influenced by the revolt of their southern neighbours, the Hereros, against the Germans. In 1905 and again in 1907 there was renewed fighting in the same region.
E. de Vasconcellos, As Colonias Portuguesas (Lisbon, 1896-1897); J. J. Monteiro, Angola and the River Congo (2 vols. London, 1875); Viscount de Paiva Manso, Historia do Congo.... (Documentos) (Lisbon, 1877); A Report of the Kingdom of Congo (London, 1881), an English translation, with notes by Margarite Hutchinson, of Filippo Pigafetta's Relatione del Reame di Congo (Rome, 1591), a book founded on the statements and writings of Duarte Lopez; Rev. Thos. Lewis, "The Ancient Kingdom of Kongo" in Geographical Journal, vol. xix. and vol. xxxi. (London, 1902 and 1908); The Strange Adventures of Andrew Battell of Leigh in Angola and the Adjoining Regions (London, 1901), a volume of the Hakluyt Society, edited by E. G. Ravenstein, who gives in appendices the history of the country from its discovery to the end of the 17th century; J. C. Feo Cardozo, Memorias contendo ... a historia dos governadores e capitaens generaes de Angola, desde 1575 até 1825 (Paris, 1825); H. W. Nevinson, A Modern Slavery (London, 1906), an examination of the system of indentured labour and its recruitment; Ornithologie d'Angola, by J. V. Barboza du Bocage (Lisbon, 1881); "Géologie des Colonies portugaises en Afrique," by P. Choffat, in Com. d. service géol. du Portugal. See also the annual reports on the Trade of Angola, issued by the British Foreign Office.