Navarre's army to the north, Willoughby took a prominent part in the capture of Vendôme early in November, of Mons (19 Nov.), of Alençon (14 Dec.), and of Falaise (27 Dec.); but his troops suffered terribly from want of food and of proper clothing. Willoughby received no money from home, and Henry of Navarre, though he treated Willoughby with much deference, declined to pay his men. Willoughby wrote to the privy council that his soldiers marched barefooted throughout the fatiguing campaign, and that more died from hunger and cold than in battle. After Henry had taken Honfleur (14 Jan. 1589-90) Willoughby obtained permission to return home with the remnants of his suffering army.
After 1590 Willoughby's poverty and ill-health determined him to live a "Coridon's life" on the continent. He was at Spa in 1594, and later on travelled in Italy (cf. Nichols, Progresses, iii. 260-1). On 7 Oct. 1594 Elizabeth sent Willoughby an autograph letter, expressing the hope that he had recovered his health, and lamenting his inability to serve her. Dr. Hawkins, writing to Anthony Bacon in February 1595-6, mentions that Willoughby had been very seriously ill at Venice, but had with great difficulty managed to remove to Vienna. ‘Very certain advertisement,’ which proved false, of the death of Willoughby reached London in June 1596 (Birch, Memoirs of Eliz. i. 327, 377, 428, 453, ii. 34). On 28 Aug. and 12 Sept. 1596 Willoughby appealed to Essex to use his influence to obtain for him the governorship of Berwick-on-Tweed. In October 1596 Willoughby returned to England. On 12 Oct. he sent to Anthony Bacon from his house in Barbican, London, a memorandum on the best way of withstanding another Spanish invasion, which is printed in Birch's Memoirs of Queen Elizabeth, ii. 164-8. Towards the end of February 1597-8 Willoughby was appointed governor of Berwick and warden of the East March. He arrived at his post on 28 April. In a letter dated 2 May, addressed to the privy council, Willoughby called attention to the inefficient state of the army in the north, and of the fortifications on the borders. In June 1599 he came into conflict with James VI of Scotland. He had sent a small force into Scotland to arrest an Englishman named Ashfield, suspected of secret hostility to Queen Elizabeth. Autograph letters on the subject passed between James and Willoughby, and it required much negotiation to satisfy the king that no disrespect had been intended him. In February 1599-1600 Willoughby was in London on leave of absence, and in intimate relations with Sir Robert Cecil. On his return to Berwick he energetically put in order the fortifications, and governed the town and district with a severity that produced a long series of disputes between him and his neighbours. Many of the latter complained to the council of the north sitting at York of Willoughby's alleged injustice, but in almost every instance the government in London approved Willoughby's action. On 22 Nov. 1600 Willoughby sent a long justification of his rigorous treatment of the garrison of Berwick to the queen. Soon afterwards he was busily engaged in watching pirate ‘Dunkirkers’ off the coast, and a ship was sent him for the service. He regularly sent information to Cecil of all that happened in Scotland, and was frequently in direct correspondence with King James. But his health was rapidly failing, and he died on 25 June 1601, protesting with his last breath his loyalty to the queen and his affection for Sir Robert Cecil. On 20 July his remains were removed from Berwick, and buried at Spilsby, Lincolnshire, in accordance with his will (dated 7 Aug. 1599). Lady Willoughby survived her husband till 1624. His eldest son Robert [q.v.] became Earl of Lindsey. His second son Peregrine entered the service of Prince Henry, and was made knight of the Bath by James I in 1610. He afterwards fought a duel with Lord Norris, in which he was wounded, and died in 1640, aged 65 (Nichols, Progresses of James I, ii. 309, 344, 676). Bertie's other children were Henry, Vere, Roger, and Catharine, who married Sir Lewis Watson, first Lord Rockingham.
Willoughby's valour, chiefly exhibited in the war in the Netherlands, and especially at the siege of Bergen, excited more admiration on the part of his contemporaries than that of almost any other soldier of the time. Glowing descriptions of his prowess appear in A True Discourse Historical of the succeeding Governors in the Netherlands (London, 1602), translated by Thomas Churchyard from the Historica Belgica by Emanuel Meteren; in Honor in his Perfection, a eulogy on the earls of Essex, Oxford, and Southampton, and on Robert Bertie, Willoughby's son, published in 1624 (a copy is in the Grenville Library); in Naunton's Fragmenta Regalia, 1653; and in Lloyd's Worthies. The spirited ballad of "Brave Lord Willoughby" relates one of Willoughby's exploits in Flanders with no very strict adherence to historical fact. The earliest copy known is an illustrated broadside in the Roxburghe collection, and cannot be dated earlier than 1640. It was very frequently reprinted in the seventeenth century, and Dr. Percy included it in his Reliques, 1765. The
