James Hamilton, Viscount Hamilton

James Hamilton, Viscount Hamilton (7 October 1786 – 27 May 1814), was a British nobleman and politician. He was the eldest son of John Hamilton, 1st Marquess of Abercorn.

Born at Petersham Lodge in Surrey, he was baptized there on 4 November 1786. His early education included tutoring by William Howley, the family's domestic chaplain, from the age of five until Howley's later appointments as Bishop of London and Archbishop of Canterbury. Hamilton subsequently attended Harrow School, where he held the rank of lieutenant and later served as captain of volunteers in 1803. He matriculated at Christ Church, Oxford, on 24 October 1805.

In the realm of politics, Hamilton was involved in electoral activities under the influence of his family. His father, the Marquess of Abercorn, intended to have Hamilton stand as a candidate for County Donegal or County Tyrone. However, the death of Abercorn’s personal agent, James Hamilton, in 1806, adversely affected the family’s influence in Donegal, leading to Hamilton's withdrawal from prospects there. Instead, Hamilton entered Parliament as a Member of Parliament (MP) for Dungannon in a by-election held in January 1807, under the sponsorship of Thomas Knox, 1st Viscount Northland, who was aligned with the Abercorn interest.

Later that year, in the general election of May 1807, Hamilton was returned as MP for Liskeard, a seat secured by his half-cousin Lord Eliot, after Abercorn declined a compromise to contest County Donegal with Earl Conyngham. Due to his age, Hamilton was underage at the time of his election.

In his private life, Hamilton married Harriet Douglas on 25 November 1809 in London. Harriet was the granddaughter of James Douglas, 14th Earl of Morton. The marriage produced three children: James Hamilton, who later became the 1st Duke of Abercorn (1811–1885); Harriet Hamilton (1812–1884), who married Admiral William Alexander Baillie-Hamilton and had children; and Lord Claud Hamilton (1813–1884).

Hamilton reportedly suffered from chronic illness, as noted by his father who described him as "long dying" during a decline in health. Despite his health issues, he was a founding member of Grillion’s Club in 1814.

He died at his residence in Upper Brook Street on 27 May 1814. His eldest son succeeded his grandfather as Marquess of Abercorn four years later. Following his death, his widow Harriet married her brother-in-law, the 4th Earl of Aberdeen, in 1815, with whom she had five additional children.