Dillon, Cecily (Cecily of St Francis) (c.1603–1653), co-foundress and first abbess of the Irish Poor Clares in Dublin, Bethlehem and Athlone, both in Co. Westmeath, was probably born at Kellefaghny, Co. Westmeath, the daughter of Theobald Dillon (qv), and his wife, Eleanor (d. 1638), daughter of Sir Edward Tuite of Tuitestown, Co. Westmeath, and widow of William Tuite of Monilea. Cecily’s father was an important Old English catholic landowner, with extensive properties in counties Westmeath, Mayo and Roscommon. Knighted by the earl of Essex (qv) in 1599, he was raised to the peerage as Viscount Dillon of Costello-Gallen in March 1622. Cecily was one of a large family which included, among others, her brothers Sir Lucas Dillon (qv), MP and member of the confederate supreme council, and Sir James Dillon (qv), a prominent army officer. Cecily and her elder sister Eleanor Dillon (qv) were among the first Irishwomen to join the convent of the English Poor Clares at Gravelines in Flanders, established in 1609 by Mary Ward, who subsequently founded the Institute of the Blessed Virgin Mary. They were professed as Sister Cecily of St Francis and Sister Eleanor Mary of St Joseph on 8 September 1622, aged nineteen and twenty-one respectively.
In May 1625, together with three other Irish nuns, the Dillon sisters left Gravelines to establish an Irish foundation at Dunkirk, where Eleanor became abbess. They soon moved on to Nieuport, where they established a community in early 1627. Ultimately their goal was to return to Ireland and, with the aid of Irish Franciscan priests, including their brothers Louis (formerly Edward) and George, they established the first Poor Clare convent in Dublin in June 1629, with Cecily as abbess. Despite the suppression of religious houses that followed a change in the Irish administration at the end of 1629, the community remained intact, possibly through the protection of another brother, Sir Lucas Dillon, a member of the Irish privy council. However, they did not remain undisturbed: on 22 October 1630 their convent was raided and they were ordered to disband. Rather than disband, the nuns went to stay temporarily at Sir Lucas's estate in Co. Westmeath. In 1631 a new convent, which they named ‘Bethlehem’, was built on an out-of-the-way portion of the Dillon estate at Ballinacliffey on the shores of Lough Ree, five miles from Athlone. Members of the Dillon family were particularly prominent in the Poor Clare community, with six of Cicely's nieces subsequently joining the order. Also included among the incumbents were the daughters of lords Westmeath, Fingall and Gormanston. The archbishop of Tuam noted in 1641 that the nuns at the convent of Bethlehem were all young gentlewomen ‘the daughters of lords and knights’, commenting that ‘they pay great sums on entry and are as absolute under the authority of the abbess as the nuns are in that much-spoken of nunnery of Lisbon’ (Kilroy, 191).
When rebellion broke out in late 1641, the Poor Clares were advised to evacuate their convent, which was sacked and burned in 1642, and they were forced to seek shelter among relatives and friends. By this time, the community had over thirty members and, as many came from Co. Galway, a small group, including Helen Martin (qv) (Sister Mary Gabriel), headed west and established a convent there, while four others went to Wexford. Cecily, however, remained in Athlone until 1653, during which time she was re-elected abbess at least five times. In 1653, in response to Oliver Cromwell's (qv) edict ‘to marry or leave the country’ (Concannon, 50), she led many of the nuns (a few remained in Galway and went into hiding) to Spain, where they had been informed they would be accommodated in religious houses. When they arrived off the coast of Galicia, their ship was held in quarantine and they were not permitted to land immediately. While still on board, Cicely, weakened and ill, died. She was buried in Spain. The small group of Poor Clares who remained in Galway re-established themselves in a house in the city, living as a secret community until they were allowed to return openly to their convent on Nun's Island in 1825.