James Cornwalsh (died 1441) was an Irish judge who held the office of Chief Baron of the Irish Exchequer. He was a political figure of considerable importance and a supporter of the Lord Lieutenant of Ireland, James Butler, 4th Earl of Ormond. He was murdered as a result of a feud over the possession of Baggotrath Castle, near Dublin.
He was the son of William Cornwalsh: as the surname suggests, the Cornwalsh family had come to Ireland from Cornwall in the fourteenth century. He was probably descended from Sir John de Cornwall, Constable of Carlow Castle in the time of Edward III. He lived mainly at Dunboyne in County Meath. He married Matilda Rochfort and by her was the father of John Cornwalsh, himself a future Chief Baron.
He was a justice of the peace for Wexford and Waterford and Deputy Admiral of Ireland. He was appointed Chief Baron in 1420 on the advice of James Butler, 4th Earl of Ormond. Irish politics was then dominated by the bitter and long-lasting feud between Ormond and the Talbot family, headed by John Talbot, 1st Earl of Shrewsbury, and Cornwalsh was a staunch adherent of Ormond. He quarreled with the Lord Chancellor of Ireland, Sir Laurence Merbury, who accused Cornwalsh of gravely slandering him before the English Council. Cornwalsh was suspended from office but restored in 1426, when the Irish Council sent him to London to give a favourable report on Ormond's tenure as Lord Lieutenant.
In 1420, when his predecessor as Chief Baron James Fitzwilliam died, Cornwalsh was appointed guardian to Fitzwilliam's young son, Phillip; with hindsight this seems an ironic choice in light of his later murderous feud with Phillip's relatives.
Baggotrath Castle was owned by Sir Edward Perrers from about 1403. Perrers was an English-born soldier and an influential statesman, who acted as Deputy to the Lord Lieutenant of Ireland, and was a close associate of James Butler, 3rd Earl of Ormond. After his only son's death in 1428 possession of the castle passed to Sir Edward's widow Joanna. By her will made in 1440 she appointed Cornwalsh her executor: she died soon afterward, and Cornwalsh entered into possession of the castle. His occupation of Baggotrath was deeply resented by Sir Edward's daughter Ismay and her husband William FitzWilliam, (a cousin of Cornwalsh's former ward Phillip); the Fitzwilliam family for centuries were the principal landowners in Dundrum, and constantly sought to expand their holdings. On 28 September 1441, when Cornwalsh had come up to Baggotrath to hold the Michaelmas assizes Fitzwilliam, according to the subsequent charges, assembled a large and warlike force, seized the castle and murdered the Chief Baron.
Given the serious nature of the crime and the social prominence of the victim, it is surprising that Fitzwilliam and Ismay were soon pardoned for killing Cornwalsh, and were even allowed to retain possession of Baggotrath castle. Elrington Ball speculated that the Crown was not satisfied about their guilt, or that Cornwalsh's actions were seen as sufficient provocation for the crime. It was in any case relatively easy to get a royal pardon from Henry VI, even for crimes as notorious as the 1455 murder of the Devonshire lawyer Nicholas Radford by Thomas Courtenay, 6th Earl of Devon, which gravely shocked English public opinion.
Elrington Ball drew the inference that "violence is indigenous to the Irish soil". There is no doubt that murder and other violent crimes were all too common in fifteenth-century Ireland, even among the ruling class- Cornwalsh's son and heir John later married Matilda, widow of Lord Galtrim, who was reputedly murdered on his own wedding day. On the other hand given the number of similar or even more heinous crimes in England, such as the Radford killing, it is perhaps fairer to conclude that there was a serious breakdown of law and order in both kingdoms, which greatly weakened the authority of the Crown.