Sir Richard FitzEustace (c.1380–1445) was an Irish statesman who briefly held the office of Lord Chancellor of Ireland.
He was born about 1380 in Coghlanstown, County Kildare. His father was Sir Maurice FitzEustace, High Sheriff of Kildare; his mother was Joan, widow of Sir James Delahyde. Another branch of the Eustace or FitzEustace family later acquired the titles Baron Portlester and Viscount Baltinglass.
He was appointed Justice of the Peace in 1408, and High Sheriff of Kildare and Constable of Ballymore Eustace in 1414. He was Member of the Irish House of Commons for Kildare and on at least two occasions was entrusted with the task of maintaining good relations with the English Crown. He was knighted before 1421.
He was appointed Lord Chancellor of Ireland in 1426 but held office for only three months; however he appears to have acted as Deputy Lord Chancellor for the next ten years, and may briefly have held office again in 1436. He served as Commissioner for the Muster in the same year.
He died in 1445.
Around 1417, he married Katherine Preston, widow of William Lawless. Since Katherine as a widow was a Royal ward Richard was obliged to obtain a royal pardon for marrying her without the Crown's consent; at the same time he was forgiven certain debts. Their son Sir Robert FitzEustace was High Sheriff of Kildare in his turn, and may also have served briefly as Lord Chancellor.
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- Journal of the County Kildare Archaeological Society Volume VII ( 1912-14)
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