A career soldier, whose bravery during the Napoleonic Wars was always praised on the hustings, Greville had been substituted for his elder brother Henry as the Castle or ‘church and state’ Member for Warwick following the latter’s succession as 3rd earl of Warwick in 1816, and his return in 1820 was assured.
Greville’s recorded activity in the 1826 Parliament is minimal. He voted against Catholic relief, 6 Mar. 1827, 12 May 1828. Following his brother’s appointment (on the recommendation of the duke of Wellington’s ministry) as a lord of the bedchamber in March 1828, he also voted with them on chancery delays, 24 Apr., and ordnance reductions, 4 July 1828. The patronage secretary Planta predicted that he would go ‘with government’ for Catholic emancipation in 1829, but he merely refrained from voting. He presented a petition for the Warwick-Napton canal bill, 27 Mar. 1829. In 1830, when Warwick’s absence from the Upper House early in the session gave rise to concern,
The ministry counted him among their ‘friends’, but he did not divide on the civil list when they were brought down, 15 Nov. 1830. He received ten days’ leave after serving on the Calne election committee, 30 Nov. He presented a Warwick petition for reform and the ballot as requested, 28 Feb., but declined to endorse it, and his vote against the Grey ministry’s reform bill at its second reading, 22 Mar. 1831, provoked a vigorous campaign to oust him.
Greville was promoted colonel of the 98th Foot in 1832 and topped the poll at Warwick at the general election that year, but was unseated on petition, 15 May 1833, after malpractices by his brother and agents were exposed.
