The Browne family had been established at Cowdray since the mid-sixteenth century, when Sir Anthony Browne‡ inherited the estate from his half-brother Sir William Fitzwilliam†, earl of Southampton, and added it to his own, already extensive, holdings in Sussex and elsewhere. Browne was well connected, several of his sisters marrying well, including Mary, who married Robert Petre†, 3rd Baron Petre, in 1620. The family remained resolutely Catholic and the 3rd viscount suffered severe financial penalties during the civil wars since he was both a recusant and a royalist. Although his debts were extensive he was nevertheless solvent, and in 1672 he was able to buy out rents which had been reserved to the crown in the original grants.
Montagu was one of the last of the Catholic peers to take his seat in the Convention Parliament, first sitting on 23 May, but thereafter he was present on 35 days before the adjournment on 13 Sept. 1660, amounting to 37 per cent of the remainder of the session; he was absent from a call of the House on 31 July 1660. He signed the address of the Sussex gentry to the king in June 1660.
Montagu was not present when the session resumed on 6 Nov. 1660, first sitting on the 13th. In all he attended on 29 days, 64 per cent of the total. On 13 Dec. he entered a protest against the vacation of Sir Edward Powell’s fines. He attended on the opening day of the new Parliament, 8 May 1661, being present on 43 days (two thirds of the sittings) before the adjournment on 30 July. He was expected to vote on 11 July 1661 in favour of the claim of Aubrey de Vere, 20th earl of Oxford, to the office of lord great chamberlain. Six days later he entered a second protest against the vacation of Sir Edward Powell’s fines. Montagu was not present when the session resumed on 20 Nov. 1661, being listed as ‘sick’ at a call of the House on 25 Nov. and first attending on 5 December. In total he was present on 28 days (22 per cent). He was absent when the 1663 session convened on 18 Feb., being excused as sick on the 23rd but attending two days later. He sat on 26 days of the session, 30 per cent of the total. His absences between 2 Mar. and 6 Apr. 1663 were covered by a proxy in favour of Charles Howard, Baron Howard of Charlton (later 2nd earl of Berkshire).
Philip Wharton, 4th Baron Wharton, listed Montagu as likely to support the attempt of George Digby, 2nd earl of Bristol, to impeach Edward Hyde, earl of Clarendon. After 7 July 1663, Montagu attended on every day of the session, bar 10 July, a crucial day in the proceedings against Clarendon. On 18 July the committee considering the bill on subsidies named him as one of the assessors of peers. He attended on the second day of the 1664 session, 21 Mar., and was then present for 24 days, 68 per cent of the total. He missed the opening of the 1664–5 session, first attending on 28 Nov. and sitting on 25 days, 52 per cent of the total. He did not attend the brief session held in October 1665, and was absent when the 1666–7 session convened on 18 Sept., being excused attendance on 1 Oct. and attending just ten days of the session, between 9 and 23 Nov., 9 per cent of the total.
Montagu was in London in June 1667, when he asked Dudley North, 4th Baron North, for a buck for the use of Sir Samuel Barnardiston‡ at the Bury St Edmunds assizes.
Montagu was present on the third day of the 1670–1 session, 21 Feb. 1670, but after a further two days in attendance he then absented himself until 4 April. From 4 Mar. to 4 Apr. his proxy was held by his nephew, William Petre, 4th Baron Petre. He was present for a further three days in April, making just six days in total before the adjournment on 11 April. He was not present when the session resumed in October 1670. On 11 Nov. he asked Richard Sackville, 5th earl of Dorset, to present his excuses to the House on account of gout, promising to attend ‘as soon as ever I am able’, and was duly excused on 14 November.
Montagu attended on the second day of the 1673 session, 5 Feb., and 14 days in all (37 per cent). He did not attend the short session of October–November 1673. He was, however, present on the opening day of the 1674 session on 7 Jan., attending on seven occasions. On the last day he attended, 27 Jan., he obtained the protection of the House against prosecution for recusancy. However, he probably found the situation threatening because on 21 Feb. 1674 he received a pass to travel abroad.
Montagu appears to have been at Newmarket in March 1675, where he had a horse running.
Although there was only a prorogation of a week, Montagu missed the first three days of the session which began on 23 May 1678, first sitting on the 27th. He sat on 21 days, 49 per cent of the total. In the same year he petitioned the king against the assumption of the title of Viscount Hereford by the descendants of Sir Walter Devereux, which would deprive the Montagus of the right to be regarded as premier viscounts of England.
Montagu also attended the prorogation of 1 Aug. 1678. He was present on the opening day of the 1678 session, 21 Oct., and attended on ten days of the session, 17 per cent of the total. Not surprisingly, on 15 Nov. 1678 he voted against the declaration against transubstantiation in the Test bill, the inclusion of which effectively barred him from Parliament. On 29 Nov. Cary Gardiner reported that Montagu had told his sister that the Commons’ address for the removal of the queen would not pass the Lords.
On 20 Dec. 1681 the attorney-general agreed to a petition of the previous May from the bailiff and burgesses of Midhurst for a renewal and confirmation of their privileges, with a grant of markets and fairs specifically to Montagu and others in trust for the inhabitants.
Montagu died on 26 Oct. 1682, and was buried at Midhurst on 2 November.
