Formal "protection" and—eventually—colonization of Nigeria resulted not only from the desire to safeguard Britain's expanding trade interests in the Nigerian hinterland, but also from an interest in forestalling formal claims by other colonial powers, such as France and Germany. By 1850 British trading interests were concentrating in Lagos and the Niger River delta. British administration in Nigeria formally began in 1861, when Lagos became a crown colony, a step taken in response to factors such as the now-illegal activities of slave traders, the disruption of trade by the Yoruba civil wars, and fears that the French would take over Lagos. Through a series of steps designed to facilitate trade, by 1906 present-day Niger was under British control.