Virtually nothing is known of Grenville’s early life. He is said to have attended Oxford, but does not appear in the college records. As a younger son he could not expect a substantial inheritance; his father Sir Bernard was prominent in local administration but not especially wealthy. The example of his famous grandfather and namesake, Sir Richard Grenville† of the Revenge, doubtless helped to point him to a military career.
Grenville’s next campaign was the 1627 Île de Ré expedition, during which he was wounded and mistakenly reported dead.
Grenville probably owed his election as a Fowey burgess in the 1628 Parliament to Buckingham’s patronage. It would have been natural for him to align himself with John Mohun* and (Sir) James Bagg II*, Buckingham’s West Country agents, and indeed he enlisted Bagg’s help when he missed the sailing of the expedition to La Rochelle in September 1628 through failure to report for duty on time.
Grenville’s marriage brought a temporary halt to his military career. He had already been granted the post of gentleman of the king’s privy chamber, presumably through Buckingham’s influence; and residence at Fitzford, his wife’s ancestral home, brought him a place in local government. However, relations with his wife quickly turned sour. In part, Mary proved too strong-willed and independent for Grenville’s liking, but money was also a major cause of contention. Grenville spent lavishly during his marriage, purchasing a baronetcy in 1630 and stocking his wardrobe with clothing worked with gold and jewels. However, Mary’s estates were apparently less extensive than he had anticipated, and in addition to his own debts, Grenville was now responsible for debts his wife had accumulated prior to their marriage, not least the considerable and long-delayed expense of suing out her livery to end her status as a royal ward. In November 1629 Grenville launched a series of law suits aimed at overturning the pre-nuptial agreement and harrassing Mary’s principal creditor, her former steward George Cuttford, who had drawn up the settlement. To protect her own position, Mary sided with Cuttford, and in 1630 came to terms with Suffolk, her erstwhile enemy, who encouraged her to separate from her husband.
Very little is known of Grenville’s movements during the next six years. By his own account he fought for Sweden in the Thirty Years War; but he also found time to enrol as a mathematics student at Leiden in early 1634. On reports of preparations for the First Bishops’ War in 1639 he returned to England and offered his services to the king, then used this show of loyalty as a platform for resuming his attacks on his wife and Suffolk. In December 1640 he secured a parliamentary committee hearing of his case, but the outcome is not known.
By the summer of 1643 Grenville was disillusioned with the war effort in Ireland, where a truce was being negotiated. Although he later asserted that he had been summoned back to England to join the king’s forces there, and was indeed arrested at Liverpool on suspicion of royalism, he initially sided with parliament, probably with a view to preserving his freedom and obtaining his arrears of pay for his Irish service.
If he was expecting instant high promotion in the royalist forces, Grenville was disappointed, though as his wife had sided with parliament he was granted her sequestered lands in Devon and Cornwall. He also secured the imprisonment of George Cuttford, and, on a dubious charge of spying, the execution of one of his wife’s lawyers.
During 1645, the royalist war effort collapsed. Whether Grenville could have done more to delay the parliamentarian advance into the West Country is open to question. He was more conscious than several of his fellow commanders of the need to maintain discipline among his troops and avoid alienating the local populations which provided the army’s pay and reinforcements. However, his uncompromising attempts to secure men and money put him at odds with the civilian authorities of Devon in particular, who accused him of lining his own pockets.
Imprisoned without trial for nearly two months, Grenville escaped to France in March during the general evacuation of royalist leaders from Cornwall. Shortly afterwards, he wrote a pamphlet, a Narrative of the proceedings of his Majesty’s affairs in the West of England, a very selective account of events since early 1645, which alleged that plots against him by his fellow commanders and the Prince’s Council had substantially contributed to the royalist defeat. Sir Edward Hyde†, a member of the Council, replied with his own version of events, which, as Lord Clarendon, he later incorporated into his History of the Rebellion. Hyde’s vituperative attack on Grenville’s conduct confirmed the latter’s prejudices, and he thereafter regarded Hyde as his greatest enemy.
