St. Joseph's Academy, the oldest Catholic educational institution in Minnesota, was founded in 1851 by four Sisters of St. Joseph of Carondelet, two hundred years after the order's founding in Le Puy, France. Leaving the mother house in St. Louis at the invitation of Bishop Joseph Cretin, the nuns believed they were to start an Indian mission; instead; they established a school dedicated to their patron saint. The first classes were held in the vestry of Father Lucien Galtier's log chapel of St. Paul from which the city took its name. A year later the school was moved into a two-story brick building; in 1859, requiring larger quarters, it was relocated on the present site of St. Joseph's Hospital.
By 1863 the academy was moved to this location. The original structure (the southwest section of this complex) is thought to be the oldest remaining Catholic schoolhouse in the state. Built of yellow limestone from local quarries, its style may be classified as "Italianate." There have been four additions to the original academy which was chiefly a boarding school until about 1870 when the growth of the city improved transportation facilities. Today the institution is a day high school for girls.