Lado Enclave The Lado Enclave was an exclave of the Congo Free State and later of Belgian Congo that existed from 1894 until 1910 , situated on the west bank of the Upper Nile in what is now South Sudan and northwest Uganda . History . Previously a part of the Ottoman - Egypt ian province of Equatoria , Lado came under the control of the British , who , under the stipulations of the 1894 British - Congolese Treaty , leased the area to King Leopold II of the Belgians for the period of his lifetime . In exchange , Leopold agreed to cede a strip of land in eastern Congo when construction of the Cape to Cairo railway was to begin . The enclave had an area of about , a population of about 250 , 000 and had its capital at the town of Lado . A Congo Free State force under Louis Napoléon Chaltin reached the Nile at the town of Bedden in the enclave in February 1897 . Chaltin defeated the Mahdist s there in the battle of Rejaf . This consolidated Léopold ' s claim to the Upper Nile , but Chaltin did not have the forces to do more , although he had been instructed to continue on towards Khartoum . The northernmost post was Kiro , on the west bank of the Nile a short distance above the British post at Mongalla . Edward Fothergill visited the Sudan around 1901 , basing himself at Mongalla between Lado to the south and Kiro to the north , but on the east shore of the river . By his account " Kiro , the most northern station of the Congo on the Nile , is very pretty and clean . Lado , the second station , is prettier still " . However , he said that although the buildings were well made , they were too closely crowded together . The Lado Enclave was important to the Congo Free State as it included Rejaf , which was the terminus for boats on the Nile . Rejaf was the seat of the Commander , the only European colonial official within the enclave , who were in place from 1897 to June 1910 . Efforts were made to properly defend Lado against any possible incursion by another colonial power , with twelve heavy Krupp fort guns installed in November 1906 . On 10 June 1910 , following Leopold ’ s death , the district became a province of the Anglo - Egyptian Sudan and in 1912 the southern half was ceded to Uganda , then a British protectorate . Later Gondokoro , Kiro , Lado and Rejaf were abandoned by the Sudanese government , and no longer appear on modern maps . CFS and Belgian Commandants of the enclave . Commandants Supérieur of Uele and the Lado Enclave 17 Feb 1897 - Nov 1897 Louis Napoléon Chaltin ( 1st time ) Nov 1897 - 15 Dec 1898 Léon Charles Edouard Hanolet ( 1st time ) 15 Dec 1898 - 1 May 1900 Jean Baptiste Josué Henry de la Lindi 1 May 1900 - Mar 1902 Louis Napoléon Chaltin ( 2nd time ) ( s . a . ) Mar 1902 - Jan 1903 Léon Charles Edouard Hanolet ( 2nd time ) ( s . a . ) Jan 1903 - 24 Mar 1904 Georges François Wtterwulghe 24 Mar 1904 - 1904 Florian Alexandre François Wacquez ( acting for Wtterwulghe to 8 May 1904 ) 1904 - May 1907 Ferdinand , baron de Rennette de Villers - Perwin ( acting to Aug 1906 ) Chief of the Lado Enclave Zone 1899 - 1900 Gustave Ferdinand Joseph Renier Commandants of the Lado Enclave 1900 - Jan 1903 Gustave Ferdinand Joseph Renier ( s . a . ) Jan 1903 - Aug 1903 Albéric Constantin Édouard Bruneel Aug 1903 - Mar 1905 Henri Laurent Serexhe Mar 1905 - Jan 1908 Guillaume Léopold Olaerts Jan 1908 - Apr 1909 Léon Néstor Preud ' homme Apr 1909 - 1910 Alexis Bertrand 1910 - Jun 1910 Charles Eugène Édouard de Meulenaer