Hamilton, Frederick (d. 1732), general and politician, has been stated to be a son of Frederick Hamilton, a gentleman with an estate at Somerset near Coleraine, Co. Londonderry, and his second wife Mary. Another reliable authority however makes him the second son of Archibald Hamilton (d. 1651 or 1652) of Millburn in Lanarkshire and his wife Mary Howard. This Scottish supporter of the parliamentary cause was hanged as a Cromwellian agent by order of Charles II; his family, compensated by the English parliament, subsequently established themselves in Ireland. It is certain in any case that Frederick had a brother, George.
From 1677 he appears as captain of an independent company in Charles II's Irish army, especially active against tories in the district of Lough Erne. He was subsequently in the regiment of Viscount Mountjoy (qv) and with other protestants he was cashiered by the earl of Tyrconnell (qv) in 1687; in early 1689 he was among the protestant officers in London seeking to enter the service of King William (qv), and was given a commission as major in the earl of Meath's regiment. He served in the war against King James (qv) in Ireland in 1689–91 and, after its conclusion, in the Flanders campaigns of King William. When the English parliament inquired into the state of Ireland in 1693 he was one of the witnesses to appear before the house of lords.
In 1692 he succeeded Meath as colonel, and his regiment distinguished itself at the siege of Namur in 1695 where he was wounded. The regiment suffered heavy losses on this occasion and was subsequently honoured by the king with the title of the ‘royal regiment of foot of Ireland’. He reached the rank of lieutenant-general before retiring from the command of his regiment in 1705. A narrative of the regiment's campaigns in Ireland and Flanders was later published by Robert Parker (qv).
He was MP for Coleraine (1713–27), and was made a privy counsellor in 1715. In the 1713 parliament, when the Irish commons defied the government by rejecting its candidate for the speakership, he led other half-pay officers (whose votes were normally at the disposal of the lord lieutenant) in the whig opposition, thus greatly irritating one of the English ministers, Viscount Bolingbroke.
He held estates in counties Tipperary, Kildare, and Londonderry; his residence was at Walworth in the latter county. In 1713 he obtained a private act of the British parliament confirming some of his land purchases.
He married Jane, elder daughter of Sir Randal Beresford and Catherine Annesley; their only child, a daughter called Jane, probably died young. His heirs were his wife's nephew, Sir Marcus Beresford, Viscount (later earl of) Tyrone; and his brother George's grandson, Frederick Carey. Frederick Hamilton died in July 1732.