to insist on an increase of their allowance, to help in sowing ill-will between the royal brothers, and the duchess was, notwithstanding her father's advice, found ready to listen to such insidious counsels. Unfortunately, however, the duke's constant succession of amours could not fail of itself to produce trouble, and the duchess had grounds enough for a jealousy which, according to Pepys (15 May 1662), was very burdensome to her consort. Soon she was said to have complained to the king and to her father about the duke's attachment to Lady Chesterfield, who in consequence had to withdraw into the country (ib. 3 Nov. 1662), where she died. Other intrigues followed with the duchess's maids of honour (Grammont, ch. ix.) and other ladies; and in one case the malevolence of the enemies of the duchess did not shrink from asserting that she had taken deadly vengeance upon her rival; a lampoon attributing the death of Lady Denham (6 Jan. 1667) to poison administered by order of the duchess was actually affixed to the door of her palace (see Marvell, Last Instructions to a Painter, l. 44, and Clarendon's House Warming, st. vii.; Works, i. 342, 385; and art. Denham, Sir John, 1615-1669).
In consequence, it was suggested (Grammont, p.274), of the duke's amour with the ugly Arabella Churchill [q. v.], the duchess was said to have resorted to a more ordinary method of revenge by countenancing the advances of Henry Sidney, the youngest son of the Earl of Leicester. He had been attached about 1665 as groom of the bed-chamber to her husband's household, and was subsequently appointed master of the horse to the duchess herself. It must be left an open question whether there actually existed between them relations of a nature'to justify the ebullition of anger in the duke, and whether this was the cause of Sidney's temporary banishment from the court (Pepys, 9 Jan. and 15 Oct. 1666; cf. Memoirs of Sir John Reresby, ed. 1873, p. 65).
Shortly after Clarendon's fall from power Pepys (3 Sept. 1667) found her and her husband alone, `methought melancholy, or else I thought so.' Under the new régime it was rumoured that a kind of cartel had been arranged between the pair and Lady Castlemaine to operate against Buckingham and Arlington (Pepys, 16 Jan.1669; cf.6 April 1668). About the same time it was noticed that she had ceased to communicate as a member of the church of England, while in conversation she displayed a marked inclination to the doctrines and usages of Rome (Burnet, i. 566). In August 1670, with a view, it has been suggested, to recover her influence over her husband, himself already to all intents and purposes a convert, she was actually received into the Roman catholic church. Her conversion was not made public till her death, though in December 1670 her 'intention' had been made known by the duke to the king. No other person except Father Hunt, a Franciscan, who reconciled her, and a lady and a servant in attendance, was privy to the transaction (Life of James II, i. 452-3); but it became known to her father (see his ' Two Letters to the Duke and Duchess of York, occasioned by her entering the Roman Catholic Religion,' in State Tracts under Charles II (1689), pp. 439-42). A paper dated 20 Aug. was left behind her after her death explaining with clearness and dignity the motives of her conversion (it will be found in Kennett, History of England, iii. 292-3). It was published by James II in 1686, together with papers of the same kind by Charles II, and produced in the same year an ' Answer ' followed by a `Reply.' Some years afterwards Father Maimbourg, in his 'Histoire du Calvinisme,' while printing the duchess's paper, attributed her change of faith to the negligence of the two prelates upon whose guidance she depended. The names of the bishops implicated are variously given as Morley, bishop of Winchester (KennettandBurnet,i.307), Archbishop Sheldon, and Blandford, bishop of Worcester. Morley vindicated himself in an 'Answer to a Letter written by a Romish Priest,' together with which he published a ' Letter to Anne, Duchess of York, a few months before her death' (Evelyn, Correspondence, iii. 401-2 and note; cf. Burnet, i. 567-8; and Rochester, ' Meditations,' &c., 1675, in Correspondence of Lords Clarendon and Rochester, 1828, ii. 647, Appendix iv.)
On 31 March 1671 the Duchess of York died, after receiving the viaticum of the church of Rome. Her husband and Queen Catherine were present during her last hours. By her desire Blandford, bishop of Worcester, on his arrival with Laurence Hyde, at that time still in doubt as to his sister's conversion, was informed of the fact by the duke. Before taking his departure the bishop contented himself with a short exhortation, on the conclusion of which the dying woman asked, `What is truth?' and in her agony reiterated the word ' truth ' before she breathed her last (Burnet, i. 568). After her death a letter arrived from her father, expostulating with her on her conversion (see for this Lister, Life of Clarendon, ii. 481-4). She had for some time suffered from the disease (cancer in the breast) of which she died. She was privately interred in the vault of Mary Queen of Scots in Henry VII's