Henry II granted the town and lands around Glin to John Fitz-Thomas Fitz-Gerald, lord of the Decies and Desmond. His descendants were to become the Earls of Desmond, who received wide powers from the English in the governing of the district. The town of Glin belonged to the Knight of Glin until 1654 when it came into the possession of Londoner, William Barker. The castle that is now the home of the present Knight of Glin was built between 1780 and 1790.
Patrick O'Connor, in his book "Exploring Limerick's Past",
believes that Glin grew as a town around this period. In those times
Glin was the centre of the Knight's estate, which consisted of about
5,600 acres. The lands consisted of the parishes of Castletown, Cappagh
and Iverus and sections of land in the parish of Croagh.
In March 1997, President Mary Robinson opened the Glin Heritage Centre, which is situated in St. Paul's Church. Up until the 1930s the Protestant community used the church as a place of worship but with the Protestant population declining, the building was neglected. The centre is opened daily from April to October.
A tradition that survives in the parish concerns weddings. When a newly married couple emerge from the Church of the Immaculate Conception, they are prevented from leaving the church. Children block the road by placing a rope across the road. The road is reopened when the children have received money from the couple