British attack during the second siege
In 1727, Bishop de Saint-Vallier, against the advice of the Minister of the Navy and the Superior of the Congrégation de Notre-Dame, sent Sister Marguerite Roy to teach in Louisbourg. In 1730, the mission received a Royal grant for the establishment of a permanent mission and the purchase of a small house. In 1734, three new Sisters replaced their companions and taught until the first siege in 1745. Louisbourg fell after six weeks of attacks by the New England troops supported by the Royal British Navy. The Sisters and their boarders were deported to the Rochefort coast in France. They went back after three years when the fortress was returned to France in accordance with the Treaty of Aix-la-Chapelle. Having lost all their belongings in Louisbourg, the Sisters rented a house where they could teach and built a new boarding school. They were once again deported to France in 1758 following the second British siege on the city.