The date of Herbert’s birth is unclear. His parents married in 1622 and his sister was born in November 1623.
Powis succeeded to the title in January 1667, and took his seat in the Lords on 23 Oct. On 4 Nov. he was appointed to a subcommittee of the committee for privileges considering the precedency of foreign (that is Scottish and Irish) nobility. When the report of the subcommittee was read on 21 Nov., Powis seems to have offered some more material for consideration. On 9 Dec. he was named to a further subcommittee to prepare a declaration and address to be offered to the committee.
Powis was present when the session resumed on 6 Feb. 1668. On 4 Mar. the House was informed that his servant, John Williams, had been arrested at the suit of Alexander Wood and detained a prisoner in the gaol of the sheriff of Shropshire, despite the fact that he had produced a protection from Powis. This being contrary to the privilege of Parliament and inconvenient for his business at the assizes, his release was ordered. On 2 May Powis chaired the committee of petitions.
Powis was absent when the 1669 session commenced on 19 Oct., and on the 26th he was excused attendance on health grounds. He first attended on the 26 Nov., being present on 11 days (31 per cent) of the session. He was present when the next session opened on 14 Feb. 1670 and attended on 38 days (just over 90 per cent) of the session before its adjournment on 11 Apr. He was named to 18 committees and was an active committee member, chairing the bill to prevent the stealing of children (29 Mar.), and chairing (28 Mar.) and reporting (29 Mar.) from the committee on the bill for ascertaining the measures of corn and salt.
Powis was absent when the session resumed on 24 Oct. 1670, first attending on the 31October. He attended on 117 days (94 per cent) of this part of the session. He was named to 38 committees, chairing (2, 13, 14 Dec.) and reporting (14 Dec.) the committees on the Worcester gaol bill; chairing (20, 27 Jan., 1 Feb. 1671) the bishops of Bangor and St Asaph lead mines bill, and reporting it (26 Jan., 8 Feb.); chairing the committee for the relief of poor prisoners (31 Jan.); chairing (1 Feb.) and reporting (15 Feb.) the bill to prevent delays in extending statutes, judgments and recognizances; chairing Booth’s estate bill (3 Mar.), and reporting it (9 Mar.); chairing an additional bill to ascertain the measures of salt and corn (18 Mar.), and reporting it (21 Mar.); and chairing the bill for paving London streets (18 Apr.), and reporting it (19 April).
Powis was present when the next session began on 4 Feb. 1673. He attended on 37 days (97 per cent) of the session before the adjournment on 29 Mar. He was named to 15 committees. He also attended when the session was resumed and Parliament prorogued on 20 Oct. 1673, and three of the four days of the session of October-November 1673.
Powis attended only the first six days of the 1674 session, 7-14 Jan., 16 per cent of the total and was named to two committees. On 8 Jan. the Lords had addressed the king to remove papists from London and its environs, to which the king assented on the 14 January. On 12 Jan. the House ordered all its members to take the oaths of allegiance, most of them doing so on 13 and 14 Jan., but Powis was not among them. Powis was, nevertheless, created an earl on 4 Apr. 1674 and introduced as such at the prorogation on 10 Nov. between his uncle, William Craven, earl of Craven, and Arthur Annesley, earl of Anglesey.
Powis was present on the opening day of the session of April-June 1675, on 13 April. On that day he appears to have been the only Catholic to have followed the lead of Anthony Ashley Cooper, earl of Shaftesbury, in the debate on the address in opposing thanks in general for the king’s speech, although he did not join the protest.
Powis was present when the 1677-8 session convened on 15 Feb. 1677. He attended on 48 days (98 per cent) of the session before the adjournment on 16 Apr., missing only one day (21 Feb). He was named to 37 committees, reporting from the committees on the bill for the preservation of fish (23 Mar.) and for taking affidavits in the country (7 Apr.). Shaftesbury described Powis as doubly vile and a papist, although this appears to have been altered to both vile and worthy.
Powis was present on each of the five days that Parliament sat from 21-28 May 1677. He did not attend the adjournments of 16 July or 3 Dec., but was present when Parliament was adjourned on 15 Jan. 1678 and when it resumed on 28 January. In this part of the session he attended on each of the 60 days (97 per cent) of the session and was named to 16 committees. On 8 and 19 Mar. 1678 he was named to manage a conference on the bill for the better regulation of fishing in several rivers. On 19 Mar. the House was informed that John Evans, a servant of Powis, and the receiver of his rents, had been detained a prisoner in Montgomery County gaol, contrary to the privilege of Parliament. Those arresting him were required to appear at the bar to answer the breach of privilege and Evans ordered to be discharged. When the House was informed on 30 Apr. that the persons concerned refused to obey the orders of the House, the serjeant-at-arms was ordered to arrest them and bring them before the bar to answer for their contempt. On 4 Apr. Powis voted Philip Herbert, 7th earl of Pembroke, guilty of manslaughter.
Powis was present on the opening day of the session of May-July on 23 May 1678, when the order for the detention of those imprisoning Evans was reissued. On 22 June three of the men were released from custody by the House but a fourth man, Gerrard Herbert, was said to have, in justification of his offence, uttered words derogatory to the authority of the House, whereupon he was committed to the Fleet prison. After the intercession of Powis, he was released on 3 July. On 1 June Powis reported from the committee for the Severn fisheries bill. On 11 and 12 July he was named to manage a conference on the bill for burying in woollen. He was present on 41 days of the session (95 per cent) and was named to 16 committees.
According to his own testimony, Powis left Powis Castle on 1 Oct. 1678 and arrived in London on the 5 October.
In his account of the alleged plot, delivered to the House on 31 Oct. 1678, Oates claimed that Powis was to have been lord treasurer if their scheme had succeeded, that he had 300 men ready to act and was prepared to risk his ‘life and fortune’ in the plot. Following a petition from Powis on 19 Nov., Arthur Capell, earl of Essex, reported to the House on 26 Nov. that nothing had been found among his papers relating to the plot and that they had been restored to him.
When the next Parliament met, the Commons revived the impeachment and on 7 Apr. 1679, presented the Lords with articles of impeachment against Powis and the other ‘popish lords’. On 8 Apr. the Lords ordered that Powis and the others were to have legal counsel to plead for them in matters of law. Powis was brought before the bar of the House on 9 Apr., where the articles of impeachment were read and the House ensured that all the indictments relating to the case were brought under the cognizance of the Lords by a writ of certiorari. Powis entered his plea in writing to the Lords on 16 Apr. 1679, proclaiming his innocence. On 23-24 Apr. the Commons declared his answer to be ‘argumentative and evasive’, whereupon on 26 Apr. Powis reaffirmed his innocence in the Lords. On 6 May 1679 the Commons informed the Lords that they were ready to make good their articles, but there were further delays and Parliament was prorogued on 27 May, before any trials could begin.
Meanwhile, the countess of Powis attempted to help her husband by becoming involved with an informer, Thomas Dangerfield, and a Catholic midwife, Elizabeth Cellier, in the promotion of the so-called ‘Meal-Tub Plot’. Although Henry Mordaunt, 2nd earl of Peterborough, and James Stuart, duke of York, believed their story, when Dangerfield realized that the scheme might backfire, he revealed the conspiracy.
Powis was still in custody in the Tower when the next Parliament opened on 21 Oct. 1680. With the focus of the impeachment proceedings on the trial of William Howard, Viscount Stafford, the House merely continued to collect evidence against Powis. On 28 Oct. 1680 Edward Turbervill testified that Powis’s chaplain, Father Morgan, had said that the ‘kingdom was in fever, but he doubted not but blood-letting would restore it to its health’. Turberville also testified to witnessing Roger Palmer, earl of Castlemaine [I], saying mass in Powis’s lodgings in Vere Street, Westminster. On 12 Nov. 1680 the Lords ordered that each of the impeached peers be kept separately from each other ‘as persons impeached and committed for high treason by law ought to be’. Dangerfield gave his testimony to the Lords on 15 Nov. 1680, in which he blamed Lady Powis and the lords in the Tower for instigating the ‘contrivance’ of the Presbyterian plot.
Powis remained in custody until after William Petre, 4th Baron Petre’s death in January 1684. He was then bailed on 12 Feb. in recongizances of £10,000 plus four sureties of £5,000 each.
The accession of James II produced a more favourable context for Powis and his fellow Catholic peers. On 13 May 1685, writs of certiorari brought the recognizances of Powis and the other imprisoned peers before the Lords on the first day of the Parliament. On the opening day, 19 May 1685, Powis, Arundel and Bellasis duly appeared and presented a petition requesting that as the testimony of Oates had been discredited, they should be discharged. On 22 May the House annulled the order of 19 Mar. 1679 continuing their impeachments. On 25 May, the attorney general informed the House that the king had directed him to enter a nolle prosequi upon the indictments against the three peers, whereupon the Lords ordered their bail to be discharged.
Powis played an increasingly visible role as an adviser to the king. In March 1686 James II granted him a special dispensation allowing him to remain in the royal presence without taking the oaths of allegiance and supremacy.
In his role as a councillor, Powis became a conduit to the king for dispensations from the rigours of the penal laws, and other favours. In about July 1686 Sir William Williams‡, the erstwhile Speaker of the Commons who was facing financial ruin for his part in publishing Dangerfield’s Narrative, wrote of Powis’s ‘late and prevalent intercession for me in my distress hath not only procured me ease in my fine’, but also hope of his ‘help to confirm his majesty’s gracious inclinations to have the proceedings of the earl of Peterborough against me stayed’.
There was also the prospect of James II appointing Powis to high office. In the second half of 1686 there were rumours that he would replace Henry Hyde, 2nd earl of Clarendon, in Ireland; he was the candidate of those Catholics opposed to the more extreme measures advocated by Richard Talbot, earl of Tyrconnel [I], such as the repeal of the act of settlement and the displacement of Protestants from the civil administration. Ailesbury later claimed that he had advised the king to send Powis to Ireland as lord lieutenant instead of Tyrconnel, but had been told that Powis had ‘a weak head’ and was not the man for the job.
In March 1687 Powis was promoted to a marquessate. On 28 Apr. 1687 Morrice’s Ent’ring Book incorrectly included him in James II’s commission to prorogue Parliament.
On 4 May 1688 he was present when the council agreed to the order for the declaration of indulgence to be read in churches.
Following the Dutch invasion, Powis was entrusted with the care of the Prince of Wales. Powis and his wife, who was the governess of the prince, were in attendance on the infant prince at Portsmouth on 26 Nov. 1688. On 7 Dec. Powis then accompanied the prince back to London. Powis and his wife then ‘fled away’ with the prince and the queen to France.
With James II now installed at St Germain, on 12 Jan. 1689 Powis was created marquess of Montgomery and duke of Powis in the Jacobite peerage, ‘the first act of the great seal since his majesty quitting the kingdom’.
As a consequence of Powis’s open adherence to the Jacobite cause, according to Roger Morrice on 16 Apr. 1689 it was moved in the Commons that his estate might be seized and given in recompense to peers like Ormond who had suffered losses in Ireland.
The forfeited Powis estates were said to be worth £10,000 per year.
Powis died on 2 July 1696 after breaking a vein in riding from Boulogne to St Germain.
