The Liberty of Thomas Court and Donore (also known as the Earl of Meath's Liberty) was one of several manors, or liberties, that existed in County Dublin, Ireland since the arrival of the Anglo-Normans in the 12th century. They were adjacent to Dublin city, and later entirely surrounded by it, but still preserving their own separate jurisdiction.
Originally the liberty was reckoned part of the barony of Uppercross. In 1774 it was erected into a separate barony called the Barony of Donore. The liberty's privileges were abolished in 1840, and the barony was abolished in 1842, when the area was transferred from the county to the city.
The origin of this liberty goes back to the founding of the church of St. Thomas in what is now Thomas St., near St. Catherine's church, in 1177. The founder was William FitzAldelm, deputy and kinsman of King Henry II. The church was dedicated to Thomas à Beckett (St. Thomas the Martyr), who had recently been murdered in his cathedral at Canterbury by followers of the king. The church, which became a rich and powerful monastery, was for the use of the Canons of the Congregation of St. Victor.
In 1195 the head of Hugh de Lacy, who had been killed in 1187, was sent by the Irish for burial to the Abbey of St. Thomas. His body was buried by the Irish in Bective Abbey, County Meath. A long controversy was then carried on between the two abbeys for his body, which was finally settled in favour of St. Thomas in 1205.
In 1380 the Parliament forbade Irishmen from professing in this abbey.
In 1538 Henry VIII dissolved the monasteries. At this time the Abbey of St. Thomas Court held 56 rectories, 2,197 acres (8.89 km2) of land, 67 houses, 47 messuages and 19 gardens. Most of the land was in Meath and Kildare. These possessions were distributed among several people, of which Sir William Brabazon (ancestor of the Earl of Meath) and Richard St. Leger were the major beneficiaries. On 31 March 1545 Sir William Brabazon was granted the lands of the Abbey, with all jurisdictions, liberties, privileges, and so on. This grant was confirmed in 1609 to Sir Edward, his son.