Forbes, Sir Arthur (1623–c.1696), 1st earl of Granard , soldier and politician, was born in Longford, son of Sir Arthur Forbes, 1st Baron Granard, of Castle Forbes, Co. Longford (originally from Aberdeenshire, Scotland), and his wife Lady Jane Lauder (née Hamilton) of the Isle of Bass, Scotland. He succeeded as 2nd Baron Granard following his father's death in a duel (1632), and defended the family seat of Castle Forbes during the 1641 rebellion.
A presbyterian royalist of Scottish extraction, during the civil war Forbes served in Scotland under James Graham, 5th earl of Montrose, being imprisoned in Edinburgh (1645–7) and remaining active in the highlands in the 1650s. He returned to Ireland in 1655. As his military activities had taken place outside Ireland, under the commonwealth Forbes retained the family estates in Longford and Leitrim, irrespective of his allegiances. He was rightly suspected of maintaining his royalism, and was briefly imprisoned in Athlone (August 1659), on suspicion of involvement in Booth's royalist rising in England. After being approached by Sir Charles Coote (qv), in January 1660 Forbes served as a crucial emissary to the exiled king and court prior to the restoration of Charles II in 1660, and afterwards benefited greatly.
Having commanded a troop of foot in February 1661, Forbes was commissioned as a captain in the regiment commanded by Coote, now earl of Mountrath, in May 1661. He was also appointed a commissioner of settlement on 25 May 1661, and was elected as MP for Tyrone (1661–6). Throughout the decade he received numerous and generous grants of land, primarily in Westmeath. A close ally and occasional emissary of James Butler (qv), 1st duke of Ormond, and his family, Forbes was generally well regarded and respected, both personally and due to his experience and knowledge of Irish affairs. He occupied a key strategic role in restoration Ireland, as his territorial base in the northern midlands, close to the Ulster border and straddling Co. Longford and Co. Roscommon, included some of the most significant areas of tory activity in the country; he would become a crucial figure in tackling them. This was also true with regards to Scottish and presbyterian communities in the north, a major security issue for successive Irish governments. This role first became evident for Forbes with his part in the suppression of Blood's plot (1663), and recurred throughout his career. From 1664 the forces under his command were stationed within his territory, mainly in Mullingar. Forbes's own religious inclinations ensured that he occasionally mediated on behalf of presbyterians, generally advocating leniency in dealings with them: for example, in 1672 he was instrumental in securing the regium donum, a royal grant to presbyterians.
Forbes was appointed to the Irish privy council in 1670, yet despite evident political skills, military affairs were his main preoccupation. He was appointed marshal of the army in July 1670 and in the absence of the viceroy, Lord Berkeley of Stratton (qv), was appointed as a lord justice (11 May–23 September 1671) alongside Archbishop Michael Boyle (qv). In 1672 he proposed reforms of the army, and in November 1672 assumed responsibility for military affairs during an illness of the new viceroy, Arthur Capel (qv), 1st earl of Essex. Essex held Forbes in high regard, consulting him closely on military matters, and he occasionally acted as an emissary and mediator on behalf of both Essex and Charles II. In 1673 Forbes was appointed to assist the investigation into the accounts of Richard Jones (qv), 1st earl of Ranelagh. However, by early 1675 he had apparently become aligned with Ranelagh. Along with Boyle, he was once again appointed as lord justice, this time in Essex's absence (25 June 1675–c.3 May 1676). On 1 April 1678 Forbes became commander of the 18th Royal Irish Foot regiment, and was created Baron Clanehugh and Viscount Granard on 23 September 1678. By this time he had acquired further lands in Dublin, Meath, Wexford, and Aberdeenshire. By the 1680s he had exhibited a considerable interest in the improvement of his estates in Longford: land had been reclaimed and orchards cultivated.
His advice on Irish affairs was still valued, but from the late 1670s Forbes was preoccupied with the mounting potential for unrest amongst presbyterians in Ulster, especially given the increase in covenanter activity in Scotland and the outbreak of rebellion there in June 1679. The possibility that such unrest could spread to Ulster ensured that Forbes became responsible for intelligence gathering and military preparations to prevent this, though the extent of his influence was occasionally doubted and he had been accused of complicity in an alleged covenanter rebellion in 1677. In April 1679 he was suggested as a possible deputy to Richard Butler (qv), earl of Arran, should the latter replace his father, Ormond, as viceroy. In September 1680 he became lieutenant-general of the army on the death of Thomas Butler (qv), earl of Ossory, a post he retained under James II (qv). He continued to be faced with the issue of presbyterian unrest and was accused of complicity in the Rye House plot in July 1683, at a time when he himself was suggesting that the imposition of the oaths of allegiance and supremacy across the north were sufficient securities in themselves. His association with the disgraced Archibald Campbell, earl of Argyll, had left him politically suspect, but this was rectified when in 1684 he testified, along with Col. Richard Talbot (qv), to the inefficiency and corruption of the Irish army. Created 1st earl of Granard on 30 December 1684, in 1685 he was responsible for securing Ulster and providing reinforcements for Scotland after the outbreak of Monmouth's rebellion in the English west country, though ultimately these were not required.
As reassuring choices for Irish protestants after James II's accession to the throne, Granard and Boyle were reappointed as lord justices for a third time (24 February 1685–9 January 1686) following Ormond's recall, with specific instructions to report on the condition of Ireland and to redress abuses in the government and army. They served until the arrival of the new viceroy, Henry Hyde (qv), 2nd earl of Clarendon. Talbot (now earl of Tyrconnell) replaced him as commander of the army in March 1686. In the same month Granard resigned his regiment to his eldest son Sir Arthur Forbes (qv), Viscount Granard, and in May was appointed lord president of the Irish privy council. The position had no precedent and, given his reluctance to accept it, remained nominal. Initially cooperative with the new regime, Granard was unhappy at its pro-catholic inclination, and although he was well regarded by Clarendon, his relations with Tyrconnell were tense. However, along with William Stewart (qv), Viscount Mountjoy, he refused to countenance a plot to seize Tyrconnell after the collapse of James II's position in England. But in 1689 Granard and Boyle provided an assessment of the condition of Ireland for Clarendon to pass on to William of Orange (qv). An advocate of the protestant interest, Granard opposed the mooted reversal of the land settlement and was barred from the privy council after James II's arrival in Ireland. He took his seat in the Irish parliament in 1689, being one of only five protestant members of the house of lords. However, despite James's having allegedly told him of his personal dislike of the Jacobite parliament's repeal of the restoration land acts, Granard – after stating his own opposition to the new policy before the house of lords – retired to Castle Forbes, where he was besieged during the Williamite war. He waited on William after his arrival in Ireland, being appointed to his privy council and given command of a force of 5,000 men with artillery. Directed towards Sligo, he secured the surrender of Sligo town to Williamite forces in September 1691. He was given authority to grant protections in Leitrim, Longford, Roscommon, and Westmeath, and was responsible for negotiating numerous submissions in and around Mullingar as the war came to a close. Granard took his seat in the 1692 Irish parliament, and afterwards retired from public life to Castle Forbes, where he died c.1696.
He married (1655) Catherine Stewart (née Newcomen), daughter of Sir Robert Newcomen, 4th baronet, of Moss Town, Co. Longford. They had five sons and one daughter. His eldest son Arthur (ironically a Jacobite) succeeded to the title. An extensive collection of family papers is retained in the Public Record Office of Northern Ireland.