The Diocese of Port-Louis is a Latin Church ecclesiastical territory or diocese of the Catholic Church located in the city of Port Louis, the capital city of Mauritius.

John Baptist Tuohill Murphy, C.S.Sp. was an Irish Roman Catholic priest in the Congregation of the Holy Ghost, who served from 1886 to 1899 as the president of the Pittsburgh Catholic College, which was later renamed Duquesne University in 1911 when it gained university status. Later, Murphy was consecrated as a bishop and administered the Roman Catholic Diocese of Port-Louis in Mauritius until his death.