Coote, Charles (d. 1709), 3rd earl of Mountrath and lord justice, was born c.1655, son of Charles Coote, 2nd earl of Mountrath, and Alice, daughter of Sir Robert Meredith, chancellor of the exchequer in Ireland. His grandfather, also Charles Coote (qv), 1st earl, was prominent on the parliamentary side in Connacht during the 1640s, becoming lord president of the province, but worked for the restoration of the monarchy in early 1660. Coote seems to have suffered considerable deprivation during the Jacobite wars, when his estate was of course forfeited. However, he was a Williamite favourite; after the war, he was granted Lord Slane's forfeited estate and also custody of the Tyrconnell estate. He carried the banner of Ireland at Queen Mary's funeral (1694).
An ally of Lord Deputy Capel (qv), he was appointed to the Irish privy council (July 1695). He soon became a prominent member of the Capel ‘faction’ in their power struggle with the supporters of the lord chancellor, Charles Porter (qv). He was a cousin of the earl of Bellomont (qv) and his sister Anne was married to Viscount Blessington (qv); both of these noblemen were also strong supporters of Capel. Mountrath opposed the election of Porter as sole lord justice after Capel's death (June 1696) and ‘withdrew in anger’ from the privy council meeting where the election took place. He was later one of three Irish peers who petitioned the English ministry, claiming the election was prejudicial to the Irish peerage. Shortly afterwards, he was appointed a lord justice himself, but in a commission with two political enemies, Porter and the earl of Drogheda. Porter, however, died in December 1696 and Drogheda and Mountrath were replaced early in 1697.
Mountrath was never to be a lord justice again, and indeed his subsequent political involvement was limited. However, in the 1697 parliamentary session, he was a member of several important committees, notably those proposing anti-catholic measures. He was one of fourteen peers who protested against the defeat of a bill that would (among other things) have restricted catholic voting rights. He died 29 May 1709 and was buried at Wing, Bucks. He married (1679) Isabella Dormer, daughter of the earl of Carnarvon. She died, allegedly ‘out of grief, pawning her last ring’ in 1691, during the family's deprivation. Two sons, Charles and Henry, succeeded to the title in their turn, but both died young. Henry was a whig MP in England 1715–20.