The Portuguese government founded the Company of Guinea to trade and set the prices of goods,[2] including gold and ivory, Melegueta pepper and slaves.

[4] Portuguese traders and exiled criminals penetrated the rivers and creeks of Upper Guinea, forming a mulatto population speaking a Portuguese-based Creole language as a lingua franca.

In the 17th century, the French established bases at Saint-Louis, Senegal, the English at Kunta Kinteh Island on the Gambia River and Dutch at Gorée.

[6] The very weak Portuguese position in Upper Guinea was strengthened by the first Marquess of Pombal who promoted the supply of slaves from this area to the provinces of Grão-Pará and Maranhão in northern Brazil.

[7] British interest in the area led to a brief attempt in the 1790s to establish a base on the island of Bolama, which showed no evidence of continuous Portuguese presence.

Although the Brazilian and Portuguese governments agreed in the 1830s to stop this traffic, it probably continued at 18th-century levels until after 1850, when the British pressured Brazil to enforce its existing ban on the import of slaves.

[9] Britain's interest in the Upper Guinea region declined with the end of the British slave trade in 1807 and became focused on Sierra Leone after the Boloma Island settlement was abandoned.

Elsewhere it was preserved, with little official assistance, by local Creole people and Cape Verde islanders, who owned small plantations (Pontus).

After the Berlin Conference of 1885 introduced the principle of effective occupation, negotiations with France led to the loss of the valuable Casamance region to French West Africa.

In 1891, António José Enes, Minister of Marine and Colonies, rationalized taxes[clarification needed] and granted concessions in Guinea, mainly to foreign companies, to increase its exports.

[21] Between 1913 and 1915, João Teixeira Pinto used Askari troops to impose Portuguese rule and crush resistance to the hut tax by destroying villages and seizing cattle, causing many to flee to Senegal or into the forests.

One paternalistic governor, Sarmento Rodrigues, promised to develop agriculture, infrastructure, and health, but did little to fight the upsurge in sleeping sickness in the 1940s and 1950s.

But on 3 August 1959, fifty striking dockworkers were killed, and after this, the PAIGC changed strategy, avoiding public demonstrations and concentrating instead on organising the rural peasants.

The PAIGC guerrillas declared the independence of Guinea-Bissau on September 24, 1973, in the town of Madina do Boe in the southeasternmost area of the territory, near the border with neighbouring Guinea.

[10] After the Carnation Revolution military coup in Lisbon on 25 April 1974, the new revolutionary leaders of Portugal and the PAIGC signed an accord in Algiers, in which Portugal agreed after a series of diplomatic meetings to remove all troops by the end of October and to officially recognize the government of the Republic of Guinea-Bissau controlled by the PAIGC, on 26 August 1974.

Muslim trade routes across the Sahara, which had existed for centuries, transported salt, kola, textiles, fish, grain, and slaves.

However, the Portuguese found they could make considerable amounts of gold transporting slaves from one trading post to another along the Atlantic coast of Africa.

As intensive plantation cultivation led to reduced soil fertility, peanuts were normally grown by peasants in Portuguese-controlled areas, who mixed them with food crops and maintained fallow periods.

[45] Before the Estado Novo period, Portugal was weak internationally and stronger powers forced it to adopt free trade policies in its colonies.

The colonies were to provide Portugal with raw materials, foreign exchange, taxes and labour, and absorb its manufactures and surplus people.

The lack of taxable export crops meant that the Portuguese administration remained unable to increase its income or its authority, in a self-limiting cycle.

Balanta rice cultivation greatly increased in the 1930s and 1940s, but the state granted legal title to the pontas to Europeans or Cape Verdeans.

He was concerned about the emphasis on peanuts, amounting to virtual monoculture, and abandonment of traditional techniques, but he urged state control and collectivisation, not smallholder farming.