Émile Gentil Émile Gentil ( 4 April 1866 – 30 March 1914 ) was a French colonial administrator , naval officer , and colonial military leader . Born at Volmunster in the department of Moselle , he later attended the École Navale , the school that formed French naval officers . As an ensign , he was assigned to conduct hydrographic soundings along the Gabonese coast from 1890 to 1892 . In 1892 he joined the colonial administration in Gabon . Missions to the African Interior . Gentil is best known for heading two military missions to conquer and consolidate territories north from modern Gabon to Chad . First Mission 1895 - 1897 . In 1895 , Gentil was ordered to find a practical route to Chad , claiming the area between for France , and hence thwarting German and British expansion . On 27 July 1895 , Gentil headed up the Congo River on the French steamship " Léon - Blot " . The ship was then dismantled and hauled by African laborers through the forest to reach navigable portions of the Oubangui , where he founded the French station at Fort - Archambault near one of Sultan Rabih az - Zubayr ' s major towns , Kouno ( now in the Chari - Baguirmi Region of Chad ) . The mission then transported the steamboat overland again to the Chari , which stretches to Lake Chad in the north . In October 1897 he convinced the Sultan Abd ar Rahman Gwaranga to sign a treaty of alliance which gave France a protectorate over the Kingdom of Baguirmi , which was then threatened by Rabih az - Zubayr , the most powerful ruler in the Chad basin . On 20 October Gentil ' s mission passed through Rabih az - Zubayr , reaching Lake Chad on the 28th . Second Mission , 1899 ( the Gentil Mission ) . After returning from France , where he had successfully lobbied the government to support further expansion , Gentil made preparations for a second Mission to seize the Chari - Baguirmi region and the area around Lake Chad from Rabih az - Zubayr . In 1899 – 1900 , the French organized three armed columns : the Gentil Mission proceeding north from French Congo , the infamous Voulet - Chanoine Mission east from Niger and the Foureau - Lamy Mission south from Algeria . The objective was to link all French possessions in Western Africa . Again supported by the steamboat " Léon - Blot " , Gentil ' s force headed to the French station at Fort - Archambault Unbeknownst to them , a previous military expedition commanded by the Lieutenant de vaisseau Henri Bretonnet and the Lt . Solomon Braun , along with Sultan Gaourang ' s Baguirmi forces had been annihilated by Rabih ' s forces in the Battle of Togbao on 17 July after attacking Rabih at Kouno . On 16 August , one of the three Senegalese tirailleurs who had survived reached Gentil and informed him of the battle . The Gentil Mission burned the town of Kouno , and confronted Rabih at the Battle of Kouno on 28 October 1899 . The French were pushed back , suffering losses , but this did not prevent them from linking up with the other missions at Kousséri on 21 April 1900 , in what today is northern Cameroon . The next day the three columns commanded by Major Amédée - François Lamy confronted Rabih az - Zubayr , who still controlled most of Chad . The French won the ensuing Battle of Kousséri , ensuring them control of most of Chad , but the battle cost both commanders their lives . Rabih ' s son succeeded him , but his empire soon disintegrated under sustained French expansion . This meant that the original expedition had now accomplished all its main aims : surveying the lands of Northern Nigeria and Niger ( contributing to a clearer Franco - British delimitation of the colonial borders ) , uniting with the Foureau - Lamy mission and destroying Rabih ' s empire , which permitted the institution in September by the French government of the Military territory of Chad . In Lamy ' s honour , Émile Gentil , who was later its first French governor , named the capital of the new French territory of Chad Fort - Lamy . In 1973 the Republic of Chad renamed it N ' Djamena . Governorship of French Congo . On 5 February 1902 Gentil was named commissioner - general of the French Congo , residing at Brazzaville . Gabon ' s second - largest city was named Port - Gentil for him .