When the Diocese of Montreal was created in 1836, Jean-Jacques Lartigue became its first titular bishop after long and painful difficulties caused by the stormy relations his Sulpician brothers had with him. He had thorough knowledge of the diocese that was entrusted to him, as he had acted as auxiliary bishop and vicar general suffragan of the Bishop of Quebec City, Bishop Plessis, for the district of Montreal, since 1820. He is remembered for his interest in education and the wisdom he showed during the political turmoil of 1837-1838.
- First Bishop of Montreal, Jean-Jacques Lartigue
- Signature of the bull of erection of the diocese by Pope Gregory XVI