Soon after Fleming was consecrated as a bishop by Scallan in the Chapel in St. John's on 28 October 1829, he implemented his Ultramontanist ideology, taking over control of the existing Catholic institution the Orphan Asylum from its lay administrators, the members of the Benevolent Irish Society. Upon Scallan's death on 29 May 1830, he automatically succeeded him as Vicar Apostolic. He then embarked on a systematic expansion of institutional Catholicism in Newfoundland. This included the construction of new parish churches, the subdivision of existing parishes into new parishes, the recruitment of Irish priests, and the introduction of two religious orders of Irish women to teach young female children. He took pains to visit outport Newfoundland, and during the winter of 1835 lived in a fishing room at Petty Harbour, administering smallpox vaccine to the whole community of Catholics and Anglicans, and remaining in quarantine with them when no physician or other clergyman would go there.