FitzGerald, Gerald fitz Maurice (c.1350–1432), 5th earl of Kildare , magnate, was eldest son of Maurice fitz Thomas FitzGerald (qv), 4th earl of Kildare, and his wife Elizabeth, daughter of Bartholomew, Lord Burghersh, and succeeded to the earldom on the death of his father (August 1390). His main sphere of activity seems to have been confined to Kildare, where he was appointed keeper of the peace in 1392. In the same year he was accused by Robert Waldby (qv), archbishop of Dublin, of trespassing on the archbishop's lands and keeping kern at Ballymore castle in violation of statute. The need to protect Kildare was driven home by his capture by Muircheartach Óg O’Connor Faly (qv) in 1398, as the O'Connor Falys became an ever-increasing threat to the peace of Co. Kildare.
However, as earl of Kildare, he could not limit his activities solely to his own lordship. He was an active member of the council in the 1390s and led troops in Leinster during Richard II's (qv) first visit to Ireland. In June 1395 he was present at discussions in England concerning royal policy in Ireland. Kildare also joined the invasion of Ulster instigated by Roger Mortimer (qv), 4th earl of March, in March 1396. He served as justiciar (September 1405–autumn 1406) after the death of James Butler (qv), 3rd earl of Ormond. However, his actions as justiciar do not appear to have pleased the lieutenant of Ireland, Thomas of Lancaster (qv), as Kildare was replaced in 1406 by Stephen Scrope (qv). Kildare was also arrested by Lancaster in August 1408 and held till he paid a fine. He was granted a full pardon in May 1409, but enjoyed no better relations with Lancaster's new deputy, Thomas Butler (qv), prior of Kilmainham. He was one of the signatories who replied to a royal request for a report on the state of Ireland in 1411.
Kildare was arrested again in June 1418 by Sir Thomas Talbot, acting as deputy for the lieutenant, John Talbot (qv), Lord Furnival. His arrest was almost certainly connected with Furnival's poor relations with the Anglo-Irish magnates in general, and the Butlers in particular. After his release from Trim castle, Kildare seems to have concentrated his attentions on his own lordship, acting as a justice in Co. Kildare throughout the 1420s.
The most pressing issue for the ageing earl was the disposition of his lands after his death. He had married twice – first (c.1381) Margaret, daughter of Sir John Rochefort, and secondly (c.1397) Agnes Darcy – but had produced no legitimate sons. He had tried to entail his lands to several of his male kin in July 1397, but in the 1420s his heir was his daughter Elizabeth. She married Sir Leonard Grey while he was lieutenant of Ireland, but was widowed in 1430. She was married again in June 1432, this time to James Butler (qv), 4th earl of Ormond. As a result the lands of the earldom passed to Elizabeth on her father's death (December 1432), while the title of earl of Kildare seems to have passed to his brother John.