Although the Portuguese arrived on Cameroon's coast in the 1500s, malaria prevented significant European settlement and conquest of the interior until the late 1870s, when large supplies of the malaria suppressant, quinine, became available. The early European presence in Cameroon was primarily devoted to coastal trade and the acquisition of slaves. The northern part of Cameroon was an important part of the Muslim slave trade network. The slave trade was largely suppressed by the mid-19th century. Christian missions established a presence in the late 19th century and continue to play a role in Cameroonian life.

Beginning in 1884, all of present-day Cameroon and parts of several of its neighbors became the German colony of Kamerun, with a capital first at Buea and later at Yaounde. After World War I, this colony was partitioned between Britain and France under a June 28, 1919 League of Nations mandate. France gained the larger geographical share, transferred outlying regions to neighboring French colonies, and ruled the rest from Yaounde. Britain's territory--a strip bordering Nigeria from the sea to Lake Chad, with an equal population--was ruled from Lagos.

In 1955, the outlawed Union of the Peoples of Cameroon (UPC), based largely among the Bamileke and Bassa ethnic groups, began an armed struggle for independence in French Cameroon. This rebellion continued, with diminishing intensity, even after independence. Estimates of death from this conflict vary from tens of thousands to hundreds of thousands.

French Cameroon achieved independence in 1960 as the Republic of Cameroon. The following year the largely Muslim northern two-thirds of British Cameroon voted to join Nigeria; the largely Christian southern third voted to join with the Republic of Cameroon to form the Federal Republic of Cameroon. The formerly French and British regions each maintained substantial autonomy. Ahmadou Ahidjo, a French-educated Fulani, was chosen President of the federation in 1961. Ahidjo, relying on a pervasive internal security apparatus, outlawed all political parties but his own in 1966. He successfully suppressed the UPC rebellion, capturing the last important rebel leader in 1970. In 1972, a new constitution replaced the federation with a unitary state.

Ahidjo resigned as President in 1982 and was constitutionally succeeded by his Prime Minister, Paul Biya, a career official from the Bulu-Beti ethnic group. Ahidjo later regretted his choice of successors, but his supporters failed to overthrow Biya in a 1984 coup. Biya won single-candidate elections in 1984 and 1988 and flawed multiparty elections in 1992 and 1997. His Cameroon People's Democratic Movement (CPDM) party holds a sizeable majority in the legislature following 2002 elections--149 deputies out of a total of 180.