The Mpongwe language identifies them as a subgroup of the Myènè people of the Bantus, who are believed to have been in the area for some 2,000 years, although the Mpongwe clans likely only began arriving in the 16th century, possibly in order to take advantage of trading opportunities offered by visiting Europeans. The Mpongwe gradually became the middlemen between the coast and the interior peoples such as the Bakèlè and Séké. From about the 1770s, the Mpongwe also became involved in the slave trade. In the 1830s, Mpongwe trade consisted of slaves, dyewood, ebony, rubber, ivory, and gum copal in exchange for cloth, iron, firearms, and various forms of alcoholic drink.
In the 1840s, at the time of the arrival of American missionaries and French naval forces, the Mpongwe consisted of 6,000-7,000 free persons and 6,000 slaves, organized into about two dozen clans. Four of these clans were preeminent; the Asiga and Agulamba on the south shore, and the Agekaza-Glass and Agekaza-Quaben on the north shore. Each of these clans was ruled by a oga, translated as "king" by Europeans, although clan leadership was largely oligarchic.
The French took advantage of longstanding inter-clan rivalry to establish a foothold; while "King Denis" (Antchouwé Kowe Rapontchombo) of the Asigas talked the French out of using his clan's area, "King Glass" (R'Ogouarowe) of the Agekaza-Glass only submitted after a bombardment in 1845, and "King Louis" (Anguilé Dowe) of Agekaza-Quaben ceded his village of Okolo and moved, leaving the French to establish Fort d'Aumale on the village's site in 1843.
The combination of slave trade suppression and direct contact by Europeans with the interior reduced Mpongwe fortunes, but at the same time missionary schools enabled young Mpongwe to work in the colonial government and enterprise. The population declined greatly as a result of smallpox, and an 1884 estimate lists only about 3,000 Mpongwe. Fang migration pressure converted many Mpongwe to urban life in the early 20th century, and they came to be leaders in both the French colony and independent Gabon.
- David Gardinier, Historical Dictionary of Gabon 2nd ed. (The Scarecrow Press, 1994) pp. 232-235