Beginning in the 5th century, the Rock of Cashel was the seat of the Kings of Munster, one of the four provinces of Ireland. During this period, St Patrick converted Aenghus, the king of the time, and made Cashel a bishopric.
Cashels greatest king however, who went on to become High King of Ireland was Brian Boru.
In 1101 Muircheartach O’Brien granted the Rock to the Church and in 1127, the bishop Cormac MacCarthy, started work on a Chapel which survives to this day and is the most remarkable Romanesque church in the country. A round tower was added about this time.
The largest building on the Rock is the 13th century cathedral and all in all the complex represents the most impressive mediaeval collection of buildings in Ireland.