Liberian Interior Pidgin English

West African Pidgin English, also called Guinea Coast Creole English, was the lingua franca, or language of commerce, spoken along the West African coast during the period of the Atlantic slave trade. British slave merchants and local African traders developed this language in the coastal areas in order to facilitate their commercial exchanges, but it quickly spread up the river systems into the West African interior because of its value as a trade language among Africans of different tribes. Later in its history, this useful trading language was adopted as a native language by new communities of Africans and mixed-race people living in coastal slave trading bases such as James Island, Bunce Island, Elmina Castle, Cape Coast Castle and Anomabu. At that point, it became a creole language.

Some scholars call this language "West African Pidgin English" to emphasize its role as a lingua franca pidgin used for trading. Others call it "Guinea Coast Creole English" to emphasize its role as a creole native language spoken in and around the coastal slave castles and slave trading centers by people permanently based there.

West African Pidgin English arose during the period when the British dominated the Atlantic slave trade in the late 17th and 18th centuries, ultimately exporting more slaves to the Americas than all the other European nations combined. During this period, English-speaking sailors and slave traders were in constant contact with African villagers and long-distance traders along thousands of miles of West African coastline. Africans who picked up elements of pidgin English for purposes of trade with Europeans along the coast probably took the language up the river systems along the trade routes into the interior where other Africans who may never have seen a white man adopted it as a useful device for trade along the rivers.

The existence of this influential language during the slave trade era is attested by the many descriptions of it recorded by early European travelers and slave traders. They called it the "Coast English" or the "Coast Jargon."

A British slave trader in Sierra Leone, named John Matthews, mentioned pidgin English in a letter he later published in a book titled A Voyage to the River Sierra-Leone on the Coast of Africa. Matthews refers to West African Pidgin English as a "jargon," and he warns Europeans coming to Africa that they will fail to understand the Africans unless they recognize that there are significant differences between English and the coastal pidgin:

...
Wikipedia