The church that came to be known as Islington United Church was established about 1818 as a Methodist society in what was then the settlement of Mimico on the Dundas highway adjacent to Mimico Creek. For several years the local Methodists met in their homes. Early settlers had frequent contact with the Indigenous people of this territory. In the early 19th century, Mary Johnston recalled being visited often by Mississaugas coming down the creek valley from the north where they had been fishing, hunting and trapping. Today, the congregation strives to restore right relations with Indigenous people.