The ineluctable presence of slavery and other forms of servitude made its mark both on the Niger and the Congo expedition. The leader of the Niger expedition selected his force from among British convict soldiers and freed African slaves who had been forced into military service. Both had reason to resent their states of servitude, though they posed different challenges. The white soldiers were undisciplined and often drunk, while the black ones were likely to desert if the expedition reached their native lands. Slavery and servitude manifest itself differently for the Congo expedition. It encountered hostility from European and African traders who suspected it was a Royal Navy anti-slaving patrol, though it also benefitted from an ex-slave who mediated on its behalf in an important slave port. Another form of servitude was the sex trade, exoticized and eroticized by explorers as the Black Venus. Both expeditions were entangled in the slave trade even as they heralded its demise.