O'Connor, Mary (Sister Mary Agnes ) (1815–59), Sister of Mercy, foundress, and social worker, was born 6 January 1815 in Kilkenny city, youngest among ten children of Patrick O'Connor and Mary O'Connor. Like other charitable women of her time she visited the sick poor and made clothes for the destitute. She entered the Convent of Mercy, Baggot St., Dublin (27 April 1838), received the habit of the Sisters of Mercy (4 September 1838), taking the religious name Sister Mary Agnes, and was professed 24 September 1840. She worked in the House of Mercy, which was a refuge for homeless women of good character, and visited the sick in their homes, and in Sir Patrick Dun's and Mercer's hospitals.
On 31 July 1844 Mother M. Agnes O'Connor was sent, on loan, as the first superioress of St Edward's Convent, 32 Queen's Square, Bloomsbury, London. On 27 January 1846 she resigned as superior to found a Convent of Mercy in New York at the request of the bishop, Dr John Hughes (qv). Mother M. Agnes and her companions left Dublin 13 April 1846 on the Montezuma from Liverpool, arriving in New York 14 May 1846. The sisters commenced visitation in the Bellevue and Harlem hospitals as well as visiting prisoners in the Tombs, Sing Sing, and Blackwell's Island penitentiary. In 1848 a religious confraternity, the League of the Sacred Heart, was established at Sing Sing. Sunday school religion classes were established for adults. A select academy was opened (15 June 1848) and a poor school (21 January 1851). A circulating library was established which provided social contact and informal instruction, and attracted a wide readership.
In 1848 a House of Mercy was set up for the reception, education, and training of immigrant Irish girls and local young women of good character. The great majority of admissions during the early years were from Ireland. Mother M. Agnes walked to the docks to meet immigrant girls and bring them to the House of Mercy, which could accommodate 100 young women. It had dormitories, large workrooms, and schoolrooms for the education and vocational training of the girls. Reading, writing, and numeracy, plain sewing, fine needlework, knitting, embroidery, dressmaking, laundry work, and kitchen work were on the curriculum. 9,054 young women were admitted during the first eighteen years. An employment bureau provided situations for non-resident applicants. 16,869 persons, including girls in the House of Mercy, were placed in situations in the first eighteen years. The House of Mercy schoolroom was also used to provide assistance, including meals, to the poor of the neighbourhood in pre-social-welfare America. Convents were established in Brooklyn (12 September 1855) and in St Louis (June 1856). Parochial and Sunday schools were opened in both cities. Permission had to be obtained in Missouri for the opening of a school for black women, as it was a slave state.
Mother M. Agnes O'Connor was superior for thirteen years until her death in the Convent of Mercy, NYC (20 December 1859). She was buried in the crypt of the original St Patrick's cathedral, Mott St., which was quite close to the convent.