Manners, Charles (1754–87), 4th duke of Rutland and lord lieutenant of Ireland, was born 15 March 1754 in England, second but eldest surviving son of John Manners, marquess of Granby, and his wife, Frances. Educated at Eton and Trinity College, Cambridge, he sat in the house of commons as MP for Cambridge University (1774–9). He married (26 December 1775) Lady Mary Isabella Somerset, daughter of the 4th duke of Beaufort; they had four sons and three daughters. His father having died in 1770, he succeeded his grandfather as 4th duke of Rutland on 29 May 1779. He used his patronage to bring William Pitt the younger into parliament as MP for Cambridge in 1780, and the two men had an enduring friendship. On 3 October 1782 he was made a knight of the garter, and when Pitt became prime minister (December 1783) he appointed Rutland his first lord lieutenant of Ireland on 12 February 1784. Arriving in Dublin on 24 February, with the initially capable Thomas Orde (qv) as his chief secretary, Rutland quickly achieved a reputation for extravagance, and was noted for his drinking, gambling, and convivial lifestyle. Perhaps this contributed to his popularity among the aristocracy and the people, for he cultivated high society, and was renowned for both the quality of his dinners and the beauty of his wife.
Despite all the ostentation, Rutland was also a shrewd politician, and made a skilful analysis of Irish politics on his arrival. In one of his regular letters to Pitt he predicted that ‘without an union Ireland will not be connected with Great Britain in twenty years' time’ (Rutland, 18–19). The most important political question during his administration was the commercial propositions, and it fell to him to manage them in Dublin. In many ways Orde was the leading figure in directing the strategy in parliament (until he was broken by the pressure), but Rutland made important efforts behind the scenes in the attempt to find a compromise that would not appear to threaten Irish legislative independence, and even pleaded with Pitt for concessions. However, he completely misjudged the mood in the Irish house of commons and the commercial bill was rejected. On 15 August 1785 he was finally forced to drop the measure after an embarrassing defeat.
He died 24 October 1787 at the viceregal lodge in Dublin, of disease of the liver and a fever, following a hectic tour of Ireland. Jonah Barrington (qv) praised Rutland for being an ‘honourable, generous and high-minded nobleman’ and noted that he and his wife were ‘reckoned the handsomest couple in Ireland’ (Barrington, ii, 224–5). But Barrington was also highly critical of his administration and accused it of being profligate and corrupt, even suggesting that the decline in morals in Irish society could be traced back to Rutland's own dissolute lifestyle.