According to some local historians, there is a possibility that Christianity pre-existed in this area prior St Patrick‘s arrival in Ireland, based on the fact that St Patrick chose to land there..
The Parish of Castletown, Co. Wexford is in the Diocese of Dublin. This is based on historical reasons going back to the Synod of Rathbreasil in 111i when boundaries of Dioceses were defined. They were based on existing territorial boundaries. The Ferns Diocese was based on the territory of Ui Chinnsealaigh while Glendalough was based on the territory of the Ui Enechglaiis territory in South East Wicklow and North East Wexford.
Castletown chapel was burned on the 11th November 1798 by yeoman and rebuilt in 1806.
The Catholic Church at Ballynacree was dedicated by Archbishop McCabe on the 8th June 1884, opened in 1885, at that time it would have been part of the Arklow parish. In 1974 it become a separate parish. It replaced a church built in 1806. (the remains of which still exist) within the Churchyard.
Castletown Churchyard is the burial place of Liam Mellows who was executed in 1922 during the Civil War. He spent part of his childhood with his grandparents at Macoyle which is located on the road between Inch and Castletown He commanded the 1st Western Division during the 1916 Rising. After the failure of the Rising he fled to America, where he arrested and detained without trial. He assisted with De Valera’s fundraising In America, returned home and was elected as a Sinn Fein MP for both East Galway and Meath constituencies. He was vehemently anti-treaty In June 1922 with fellow republicans entered the Four Courts, which was occupied by anti-treaty forces. After two days they surrendered. Imprisoned in Mountjoy Jail he was executed along with three others as reprisal for the murder of Sean Hales. He expressed the wish in his last letter to be buried in Castletown.
There are two fine Celtic monuments in the Churchyard to Sir David Kelly. Born in 1891 in Australia to parents of Ulster stock in he fought in the First World War and was awarded the Military Cross. After the First World war he entered the Diplomatic Service and was appointed Minister to Switzerland from 1940-2. He then appointed as Ambassador to Argentina, Turkey and to the Soviet Union from 1949-1951. After the death of his first wife he married Marie-Noele de Jourda de Vaux. As Marie Noelle Kelly she wrote five books including her autobiography Dawn to Dusk, 1960. Sir David Kelly was the author of five books, his best known being “The Ruling Few, 1952, The Hungary Sheep: a discussion of modern civilisation, 1955.