St. Mary's Church has the distinction of being the first Catholic Church in Elgin. Originally established as an academy for women of all denominations in 1880, The Sisters of Charity set out to mold minds "...in the ways of rectitude and virtue, thus developing the moral and intellectual qualities simultaneously".

The church began construction in 1896 and took three years to complete. Once finished, it was the most costly church erected in the city. Since it predated all other Catholic institutions, students came from a wide geographic area, as well as Elgin and South Elgin. St. Mary’s Church parishioners were largely Irish and other Catholic schools and churches, such as St. Joseph’s, would be built so that parishioners could withdraw from the Irish domination.