Coote was returned to the
Irish House of Commons for
Queen's County in 1776, a seat he held until 1783, and then represented
Maryborough until 1798. He once again sat for Queen's County from 1798 to 1800, when the Irish Parliament was abolished. He served as Commissioner of Barracks of Ireland between 1788 and 1789, as Commissioner of Accounts of Ireland between 1789 and 1795, as Commissioner of Customs of Ireland between 1795 and 1799 and as Commissioner of Excise of Ireland between 1799 and 1806 He was appointed
High Sheriff of Queen's County for 1791–92, and
Colonel of the
Queen's County Militia on 22 January 1799. In 1801 he was returned to the British Parliament for
Queen's County. Lord Mountrath died in 1802 and Charles Coote succeeded as 2nd Baron Castle Coote according to the special remainder (the earldom became extinct; see
Coote baronets). Coote was consequently forced to resign his seat in Parliament as Irish peers were not allowed to represent Irish constituencies in Parliament. Lord Castle Coote served as a Commissioner of Customs of Ireland between 1802 and 1803 and as First Commissioner between 1806 and 1823. ==Family==