The colonial government was, in particular, interested in fostering trade as this provided it with its main source of revenue, in the form of customs duties and other taxes.
The treaties usually committed an African chief to protect merchants and maintain peaceful relations with his neighbours so that trade would not be disturbed; in return, the British would pay him a gift or annual stipend.
The military expeditions were against chiefs who acted detrimentally to the colony's business interests by evicting traders, restricting trade, or warring with neighbours.
In addition to commercial and anti-slave-trade motives for the British incursions into the Sierra Leone hinterland, military officers posted to Sierra Leone needed battle victories to enhance their reputations; and British felt culturally superiority and assumed that Europeanising natives was a proper and upright activity.
In 1898, the Sierra Leone chiefs sought to free themselves of British control in a rebellion called the Hut Tax war.