In 1912 the missions of Burundi, formerly part of the Vicariate of Unyanyembe, were joined with the missions of
Rwanda to form the new
Apostolic Vicariate of Kivu, with Hirth as the first vicar apostolic. South Nyanza now consisted only of the regions of
Bukoba and
Mwanza to the south of
Lake Victoria. On 12 December 1912 Sweens succeeded Hirth as vicar apostolic of South Nyanza. On 15 January 1915 the territory was renamed the Vicariate Apostolic of Victoria-Nyanza (now the
Archdiocese of Mwanza). The vicariate was severely disrupted during
World War I (1914–18). In June 1915 Sweens was in the entrance of the church of Bukoba when the British fired a shell at the roof during a
raid on Bukoba, which exploded on the spot where Sweens had been standing a moment before. British forces occupied Bukoba in June 1916 and Mwanza in July 1916. Fighting in the south continued until the armistice in 1918, but from mid-1916 South Nyanza was under British control. In 1917 Sweens ordained the first four priests at Rubya. During the 1920s discipline broke down in the major seminary at Rubya. Sweens was constantly traveling between the vicariate missions, and delegated all authority to the teachers at the seminary. Apparently he was not aware of the problems. Eventually an inquiry was launched that resulted in dividing the vicariate and dissolving the major seminary. Exhausted by the work, Sweens submitted his resignation in 1928, and this was accepted the same year. He left office on 15 November 1928. In April 1929 Sweens' former vicariate was divided into two more manageable units, the vicariates of
Bukoba and
Mwanza. After his retirement, Sweens stayed on at
Rubya until his death. He died on 12 April 1950. ==References==