Serving under these European officers was an ethnically-mixed African soldiery, who eventually became comparable to the askaris fielded by other European colonial powers. Many were recruited or conscripted from “warrior tribes” in the Haut-Congo, others were mercenaries drawn from Zanzibar and West Africa (Nigerian Hausas). The role required of the "Force Publique" was that of both defending Free State territory and of internal pacification. In the 1890s, the "Force Publique" defeated the African and Arab slavers in the course of the Congo–Arab War (1892–1894), which resulted in tens of thousands of casualties.