Northern Nigeria was a British protectorate which lasted from 1900 until 1914 and covered the northern part of what is now Nigeria. The protectorate spanned 660,000 square kilometres (255,000 sq mi) and included the states of the Sokoto Caliphate and parts of the former Bornu Empire, conquered in 1902. The first High Commissioner of the protectorate was Frederick Lugard, who actively suppressed revolutions and created a system of administration built around native authorities.