Sidney, Philip (1619–98), Viscount Lisle , 3rd earl of Leicester , soldier, and politician, was born 10 January 1619 in London, eldest son of Robert Sidney (1595–1677), 2nd earl of Leicester, and his wife, Dorothy (baptised 1598, d. 1659), eldest daughter of Henry Percy, 9th earl of Northumberland. He also had a number of notable siblings: his younger brothers included the political theorist Algernon Sidney and the whig politician and lord lieutenant of Ireland Henry Sidney (qv), earl of Romney. Until his own accession to the earldom, on the death of his father (1677), Philip bore the courtesy title Viscount Lisle. It is by this title that he is most often mentioned in much of the historiography on seventeenth-century Ireland.
Lisle spent his teenage years travelling between England and the continent, accompanying his father (with whom he was on poor terms) on diplomatic missions to Denmark (1632) and France (1636). He matriculated at Christ Church, Oxford, in 1634. During the late 1630s he became involved in the crises of the Stuart kingdoms, and in 1640 served in the second bishops’ war and was returned to both the short and long parliaments as MP for Yarmouth.
When the Irish uprising broke out Lisle was ordered to Ireland by his father, who had previously been appointed lord lieutenant in June 1641 in succession to Thomas Wentworth (qv). Before coming to Ireland he subscribed in excess of £2,000 under the terms of the adventurers’ act, passed at Westminster in February 1642. He was given command of a regiment of 600 horse, which did not arrive in Ireland until June, and landed at Dublin in April 1642. Soon after, he became involved in military conflict in Leinster and southern Ulster. In May he joined with troops commanded by Charles Coote (qv) and helped to drive a contingent of rebels away from the vicinity of Naas. Appointed lieutenant-general of the horse in September 1642, he took outright command of a force of 1,500 soldiers and relieved Athboy, which was threatened by confederate forces. Immediately after this, and before the end of the fighting season, he commanded a plundering expedition deep into confederate quarters to the north of Dublin. He advanced as far as Monaghan on this expedition, attacking a number of confederate garrisons on the way and destroying many of their supplies, before returning to Dublin in October 1642.
Despite these successes, Lisle's campaigning was not trouble-free. Prior to his march into Monaghan, in July 1642 he had, along with a number of other officers, appealed to the king's commissioners for Irish affairs for payment of arrears due for service in Britain and Ireland. Matters did not improve, and in May 1643 he signed a petition addressed to the English parliament, complaining of the shortfall in the supply of officers and regiments in Ireland. He was also at loggerheads with the commander of the royal army in Ireland, Thomas Butler (qv), earl of Ormond; with the outbreak of the English civil war in August 1642, Lisle followed his father in taking the English parliament's side, while Ormond took the side of Charles I. As a result, parliament's sympathisers in Dublin castle began to favour Lisle in opposition to Ormond. He received a custodium of lands in Leixlip (worth £2,000 a year) in 1642 and was admitted to the meetings of the Irish privy council, despite not being sworn of the privy council. However, Ormond successfully lobbied Charles I to have Lisle excluded from these deliberations.
When a decision was taken early in 1643 to attack the confederate towns of New Ross and Wexford, Lisle was proposed as commander by the pro-parliament lords justices, but Ormond refused to countenance this. Thus it was Ormond who led the royal army to victory over the catholic confederate forces at the battle of New Ross on 18 March 1643. Lisle was also present and was subsequently accused of misconduct at this engagement by Ormond's chaplain. Soon afterwards, when Ormond opened negotiations with the confederate catholics for a military cessation, Lisle returned to England. The reasons he gave, expressed in a letter to his father, were his belief that nothing further could be achieved in Ireland, and a fear that an oath against supporting the English parliament was about to be imposed on army officers in Ireland. Furthermore, relations between him and Ormond had collapsed. Three years later, in 1646, Lisle ruled out any possibility of ever cooperating with Ormond again.
On his return to England, he was briefly arrested before being released and voted £1,000 by parliament for his services in Ireland. He resumed his seat in parliament and continued to exercise some influence on affairs in Ireland, associating himself closely with a group of exiled Irish protestant landowners in London who lobbied for the English reconquest of Ireland. In August 1644 he sat on two committees, one appointed to hear a petition from the committee of adventurers in London, and the other to hear a petition from the protestants of Munster; he was also frequently consulted by the English parliament's committee on Irish affairs (the so-called ‘Derby house committee’). He was an adherent of the Independent faction at Westminster, a group that advocated radical religious views, a drastic curtailment of the crown's powers, and, more pertinently, the establishment of English hegemony over Ireland and Scotland. The Independents were opposed by the more moderate presbyterian faction, with whom Ormond had strong ties.
In late January 1646 the Independents secured Lisle's appointment by the English parliament as lord lieutenant of Ireland. This promotion was designed to exclude the Scots from any influence over Irish matters; previously parliament had authorised a Scottish military intervention in Ulster and had envisaged that the reconquest of Ireland would be a joint Anglo–Scottish affair. It was also designed to deny the validity of Ormond's title as lord lieutenant, which had been bestowed on him by the king. Lisle's elevation to the lord lieutenancy of Ireland coincided with the publication of The Irish rebellion by one of his allies, Sir John Temple (qv) (1600–77). This work, which appears to have faithfully reflected the intentions of Lisle and his circle, advocated the expropriation of all catholic proprietors in Ireland. As well as condemning the barbarity of the Irish catholics, Temple argued that the native protestants could not be trusted either, an allusion to Ormond.
Although Sidney's commission was dated 9 April 1646, he did not go to Ireland that year owing to political distractions in England and to a short-lived rapprochement between Ormond and the English parliament in the autumn. He eventually arrived in Munster on 1 February 1647, bringing with him a force of 120 horse and 5,000 foot. The choice of Munster was a deliberate snub to the protestant forces under Ormond at Dublin and to the Scottish forces based in Ulster. However, the commander of the protestant forces in Munster, Murrough O'Brien (qv), Lord Inchiquin, was a supporter of the presbyterians and accurately regarded Lisle's arrival as an attempt to supplant him in the province. For his part Lisle distrusted Inchiquin due to his Gaelic background and his former support of Ormond. He immediately ordered the removal of Irish protestant soldiers and officers from key garrisons across the province. His patronage of radical Independent clergymen also antagonised the more orthodox local protestants.
Lisle's high-handed actions quickly produced a conservative backlash in Scotland and England, while Ormond's decision in February 1647 to resume negotiations with parliament for the surrender of Dublin further strengthened the moderates in London. By the end of March 1647 the presbyterians had wrested control of the Westminster parliament from Lisle's allies. His commission as lord lieutenant was only for one year, and parliament now declined to renew it. As a result, he returned to England when his commission expired on 15 April 1647, having achieved little during his time in Munster. However, in August the English army intervened in support of the Independents and effectively installed them in power. Lisle's signature stood at the head of a list of MPs who expressed their approval of the army's actions.
He made no attempt to regain his position as lord lieutenant and had little subsequent involvement in Irish affairs. Appointed to the commission to try Charles I in 1649, he wisely did not take part in the proceedings. Thereafter he was a prominent member of the republican and Cromwellian regimes, sitting on various councils of state for most of the 1650s. He was one of the adventurers who drew for lands in Co. Laois in 1653 (receiving an allotment worth £1,800) and in Co. Westmeath in 1654 (receiving two allotments, one in an unknown location but worth £600, and the second of unknown value in the barony of Kilkenny West), and was appointed to a commission investigating the claim of the London companies to be restored to their holdings in the plantation of Ulster. However, he showed no interest in his public duties and had very little political influence.
The restoration of the Stuart monarchy in 1660 effectively ended his political career. The latter part of his life was dominated by disputes with his family, arising from his bitter relationship with his father. Although he succeeded as 3rd earl of Leicester on his father's death (1677), the 2nd earl had saddled his inheritance with bequests of £20,000 to £29,000 to his brothers Algernon and Henry. This led inevitably to legal action between the siblings and a prolonged feud that was only settled in 1683, shortly before Algernon was executed for treason. Lisle died at Leicester House, London, on 6 March 1698.
He married (May 1645) Lady Catherine, daughter of William Cecil, 2nd earl of Salisbury. She died in 1652 but not before bearing him a son, Robert. He also fathered three sons and a daughter out of wedlock.