Born on May 4, 1820, in Naas (Republic of Ireland), Ellen Dease was one of five children of Oliver Dease and Anne Nugent. She attended a seminary for young ladies and studied mainly in Paris. Fluent in French and Italian, she was also an accomplished musician. At the age of twenty-five, Ellen entered Loretto (now Loreto) Abbey, Rathfarnham, and became known as Mother Teresa.
At the invitation of Bishop Michael Power of Toronto, Loreto Rathfarnham sent five sisters, Mother Teresa being one, to his diocese in 1847. They arrived on September 16th, in the midst of the typhus epidemic. The first school was opened on September 29th, with Mother Teresa teaching languages and music. In 1848 a free school for poor children was opened with Mother Gertrude (Mary Fleming) as teacher, the first sister to teach in the separate schools of the city. On March 19, 1851, Mother Teresa was named superior and entered on the long term of office that gave her the title of foundress of the Institute in America.
In the spirit of Mary Ward, founder of the Institute of Blessed Virgin Mary, Teresa Dease focused on the education of young women. She also exhibited the charism of ‘contemplatives in action’. Teresa opened thirteen houses with schools attached. From these houses, the sisters also went out to teach in the local parishes. Some of the first Catholic elementary schools were held in church basements.
Mother Teresa always insisted that her teachers be competent in their field and well prepared for their classes. By the 1870’s, her sisters were attending Normal School in order to prepare their students for the Provincial Departmental Examinations. She was able to adapt herself and the Institute to the changing needs of the Church and society. Religious education and faith formation was always the core of the curriculum which included history, languages, English literature and the arts.
Mother Teresa was given affection and respect by countless friends, both Roman Catholic and Protestant; by pupils, who at the time of her death numbered thousands; and by the sisters of the Institute in Ireland and in Canada.