Ashbourn, Ellis de (c.1290–c.1357), chief justice of the justiciar's bench, was the son of Roger de Ashbourn, one-time provost of Dublin and serjeant-at-law. He spent some of his turbulent early life in Northamptonshire in England and was involved in a feud with the fitz Warins after an incident (December 1309) when he was accused, along with others, of looting and burning one of their manors. By July 1311 he had returned to Ireland and was granted a pardon for waylaying and castrating a traveller on his way to Dublin. He attached himself to the household of John de Hotham (qv), bishop of Ely, and accompanied him on a visit to Rome (1317).
In Ireland in 1322, styled ‘king's yeoman’, he was appointed marshal of the important eyre of Meath. Politically adept, in 1326 he was nominated to instigate proceedings against Alexander Bicknor (qv), archbishop of Dublin, and Walter Islip (qv), treasurer of the Dublin exchequer. He obtained the lucrative position of seneschal of the archbishop's manors of Swords, Finglas, and the liberty of St Sepulchre.
From 4 June 1327 to 2 March 1329 he acted as a justice of the justiciar's bench, and was then appointed chief justice till 8 June 1331, reappointed chief justice (8 March 1337), dismissed (10 August), and again reappointed from 12 September 1338 to 26 November 1341, when he was once more dismissed, paid a substantial fine, and was restored. In 1343 he seems to have lost his post, and early in 1344 his lands were confiscated by the new justiciar, Ralph de Ufford (qv). Despite spending most of June and July in England, apparently pleading his case before the king, his remaining chattels were seized and he was imprisoned in Dublin Castle. On 24 June 1346, at the request of a group of the king's Irish ministers, he was released. The remainder of his life was spent in relative obscurity and he died c.1357.
Throughout his period first as justice and then as chief justice, he was the recipient of a large number of royal favours, was granted a number of sinecures, and built up a substantial landed interest in Co. Dublin. Royal hostility to the excessive acquisitiveness of crown officials, and to the blatant corruption of the Dublin administration, led to his downfall.
He married (c.1325) Elizabeth (family name unknown); they had two sons and a daughter.