Although Henry VII. had neither disturbed the Earl in his governments, nor his brother, Lord Thomas, as Chancellor, it was not to be expected that he could place entire confidence in the leading Yorkist family among the Anglo-Irish. The restoration of the Ormond estates, in favour of Thomas, seventh Earl, was both politic and just, and could hardly be objectionable to Kildare, who had just married one of his daughters to Pierce Butler, nephew and heir to Thomas. The want of confidence between the new King and his Deputy was first exhibited in 1486, when the Earl, being summoned to attend on his Majesty, called a Parliament at Trim, which voted him an address, representing that in the affairs about to be discussed, his presence was absolutely necessary. Henry affected to accept the excuse as valid, but every arrival of Court news contained some fresh indication of his deep-seated mistrust of the Lord Deputy, who, however, he dared not yet dismiss.

The only surviving Yorkists who could put forward pretensions to the throne were the Earl of Lincoln, Richard's declared heir, and the young Earl of Warwick, son of that Duke of Clarence who was born in Dublin Castle in 1449. Lincoln, with Lord Lovell and others of his friends, was in exile at the court of the dowager Duchess of Burgundy, sister to Edward IV.; and the son of Clarence—a lad of fifteen years of age—was a prisoner in the Tower. In the year 1486, a report spread of the escape of this Prince, and soon afterwards Richard Symon, a Priest of Oxford, landed in Dublin with a youth of the same age, of prepossessing appearance and address, who could relate with the minutest detail the incidents of his previous imprisonment. He was at once recognized as the son of Clarence by the Earl of Kildare and his party, and preparations were made for his coronation by the title of Edward VI. Henry, alarmed, produced from the Tower the genuine Warwick, whom he publicly paraded through London, in order to prove that the pretender in Dublin was an impostor. The Duchess of Burgundy, however, fitted out a fleet, containing 2,000 veteran troops, under the command of Martin Swart, who, sailing up the channel, reached Dublin without interruption. With this fleet came the Earl of Lincoln, Lord Lovell, and the other English refugees, who all recognized the protege of Father Symon as the true Prince. Octavius, the Italian Archbishop of Armagh, then residing at Dublin, the Bishop of Clogher, the Butlers, and the Baron of Howth, were incredulous or hostile. The great majority of the Anglo-Irish lords, spiritual and temporal, favoured his cause, and he was accordingly crowned in Christ Church Cathedral, with a diadem taken from an image of our Lady, on the 24th of May, 1487; the Deputy, Chancellor, and Treasurer were present; the sermon was preached by Pain, Bishop of Meath. A Parliament was next convoked in his name, in which the Butlers and citizens of Waterford were proscribed as traitors. A herald from the latter city, who had spoken over boldly, was hanged by the Dubliners as a proof of their loyalty. The Council ordered a force to be equipped for the service of his new Majesty in England, and Lord Thomas Fitzgerald resigned the Chancellorship to take the command. This expedition—the last which invaded England from the side of Ireland—sailed from Dublin about the first of June, and landing on the Lancashire shore, at the pile of Foudray, marched to Ulverstone, where they were joined by Sir Thomas Broughton and other devoted Yorkists. From Ulverstone the whole force, about 8,000 strong, marched into Yorkshire, and from Yorkshire southwards into Nottingham. Henry, who had been engaged in making a progress through the southern counties, hastened to meet him, and both armies met at Stoke-upon-Trent, near Newark, on the 16th day of June, 1487. The battle was contested with the utmost obstinacy, but the English prevailed. The Earl of Lincoln, the Lords Thomas and Maurice Fitzgerald, Plunkett, son of Lord Killeen, Martin Swart, and Sir Thomas Broughton were slain; Lord Lovell escaped, but was never heard of afterwards; the pretended Edward VI. was captured, and spared by Henry only to be made a scullion in his kitchen. Father Symon was cast into prison, where he died, after having confessed that his protege was Lambert Simnel, the son of a joiner at Oxford.

Nothing shows the strength of the Kildare party, and the weakness of the English interest, more than that the deputy and his partizans were still continued in office. They despatched a joint letter to the King, deprecating his anger, which he was prudent enough to conceal. He sent over, the following spring, Sir Richard Edgecombe, Comptroller of his household, accompanied by a guard of 500 men. Sir Richard first touched at Kinsale, where he received the homage of the Lords Barry and de Courcy; he then sailed to Waterford, where he delivered to the Mayor royal letters confirming the city in its privileges, and authorizing its merchants to seize and distress those of Dublin, unless they made their submission. After leaving Waterford, he landed at Malahide, passing by Dublin, to which he proceeded by land, accompanied with his guard. The Earl of Kildare was absent on a pilgrimage, from which he did not return for several days. His first interviews with Edgecombe were cold and formal, but finally on the 21st of July, after eight or ten days' disputation, the Earl and the other lords of his party did homage to King Henry, in the great chamber of his town-house in Thomas Court, and thence proceeding to the chapel, took the oath of allegiance on the consecrated host. With this submission Henry was fain to be content; Kildare, Portlester, and Plunkett were continued in office. The only one to whom the King's pardon was persistently refused was Sir James Keating, Prior of Kilmainham.

In the subsequent attempts of Perkin Warbeck (1492-1499), in the character of Richard, Duke of York, one of the Princes murdered in the tower by Richard III., the Anglo-Irish took a less active part. Warbeck landed at Cork from Lisbon, and despatched letters to the Earls of Kildare and Desmond, to which they returned civil but evasive replies. At Cork he received an invitation from the King of France to visit that country, where he remained till the conclusion of peace between France and England. He then retired to Burgundy, where he was cordially received by the Duchess; after an unsuccessful descent on the coast of Kent, he took refuge in Scotland, where he married a lady closely allied to the crown. In 1497 he again tried his fortune in the South of Ireland, was joined by Maurice, tenth Earl of Desmond, the Lord Barry, and the citizens of Cork. Having laid siege to Waterford, he was compelled to retire with loss, and Desmond having made his peace with Henry, Warbeck was forced again to fly into Scotland. In 1497 and '8, he made new attempts to excite insurrection in his favour in the north of England and in Cornwall. He was finally taken and put to death on the 16th of November, 1499. With him suffered his first and most faithful adherent, John Waters, who had been Mayor of Cork at his first landing from Lisbon, in 1492, and who is ignorantly or designedly called by Henry's partizan "O'Water." History has not yet positively established the fraudulency of this pretender. A late eminently cautious writer, with all the evidence which modern research has accumulated, speaks of him as "one of the most mysterious persons in English history;" and in mystery we must leave him.

We have somewhat anticipated events, in other quarters, in order to dispose of both the Yorkist pretenders at the same time. The situation of the Earls of Kildare in this and the next reign, though full of grandeur, was also full of peril. Within the Pale they had one part to play, without the Pale another. Within the Pale they held one language, without it another. At Dublin they were English Earls, beyond the Boyne or the Barrow, they were Irish chiefs. They had to tread their cautious, and not always consistent way, through the endless complications which must arise between two nations occupying the same soil, with conflicting allegiance, language, laws, customs, and interests. While we frequently feel indignant at the tone they take towards the "Irish enemy" in their despatches to London—the pretended enemies being at that very time their confidants and allies—on farther reflection we feel disposed to make some allowance on the score of circumstance and necessity, for a duplicity which, in the end, brought about, as duplicity in public affairs ever does, its own punishment.

In Ulster as well as in Leinster, the ascendency of the Earl of Kildare over the native population was widespread and long sustained. Con O'Neil, Lord of Tyrone, from 1483 to 1491, and Turlogh, Con and Art, his sons and successors (from 1498 to 1548), maintained the most intimate relations with this Earl and his successors. To the former he was brother-in-law, and to the latter, of course, uncle; to all he seems to have been strongly attached. Hugh Roe O'Donnell, Lord of Tyrconnell (1450-1505), and his son and successor, Hugh Dhu O'Donnell, (1505-1530), were also closely connected with Kildare both by friendship and intermarriage. In 1491, O'Neil and O'Donnell mutually submitted their disputes to his decision, at his Castle of Maynooth, and though he found it impossible to reconcile them at the moment, we find both of these houses cordially united with him afterwards. In 1498, he took Dungannon and Omagh, "with great guns," from the insurgents against the authority of his grandson, Turlogh O'Neil, and restored them to Turlogh; the next year he visited O'Donnell, and brought his son Henry to be fostered among the kindly Irish of Tyrconnell. In the year 1500 he also placed the Castle of Kinnaird in the custody of Turlogh O'Neil. In Leinster, the Geraldine interest was still more entirely bound up with that of the native population. His son, Sir Oliver of Killeigh, married an O'Conor of Offally; the daughter of another son, Sir James of Leixlip, (sometimes called the Knight of the Valley) became the wife of the chief of Imayle. The Earl of Ormond, and Ulick Burke of Clanrickarde, were also sons-in-law of the eighth Earl, but in both these cases the old family feuds survived in despite of the new family alliances.

In the fourth year after his accession, Henry VII., proceeding by slow degrees to undermine Kildare's enormous power, summoned the chief Anglo-Irish nobles to his Court at Greenwich, where he reproached them with their support of Simnel, who, to their extreme confusion, he caused to wait on them as butler, at dinner. A year or two afterwards, he removed Lord Portlester, from the Treasurership, which he conferred on Sir James Butler, the bastard of Ormond. Plunkett, the Chief-Justice, was promoted to the Chancellorship, and Kildare himself was removed to make way for Fitzsymons, Archbishop of Dublin. This, however, was but a government ad interim, for in the year 1494, a wholly English administration was appointed. Sir Edward Poynings, with a picked force of 1,000 men, was appointed Lord Deputy; the Bishop of Bangor was appointed Chancellor, Sir Hugh Conway, an Englishman, was to be Treasurer; and these officials were accompanied by an entirely new bench of judges, all English, whom they were instructed to instal immediately on their arrival. Kildare had resisted the first changes with vigour, and a bloody feud had taken place between his retainers and those of Sir James of Ormond, on the green of Oxmantown—now Smithfield, in Dublin. On the arrival of Poynings, however, he submitted with the best possible grace, and accompanied that deputy to Drogheda, where he had summoned a Parliament to meet him. From Drogheda, they made an incursion into O'Hanlon's country (Orior in Armagh). On returning from Drogheda, Poynings, on a real or pretended discovery of a secret understanding between O'Hanlon and Kildare, arrested the latter, in Dublin, and at once placed him on board a barque "kept waiting for that purpose," and despatched him to England. On reaching London, he was imprisoned in the Tower, for two years, during which time his party in Ireland were left headless and dispirited.

The government of Sir Edward Poynings, which lasted from 1494 till Kildare's restoration, in August, 1496, is most memorable for the character of its legislation. He assembled a Parliament at Drogheda, in November, 1495, at which were passed the statutes so celebrated in our Parliamentary history as the "10th Henry VII." These statutes were the first enacted in Ireland in which the English language was employed. They confirmed the Provisions of the Statute of Kilkenny, except that prohibiting the use of the Irish language, which had now become so deeply rooted, even within the Pale, as to make its immediate abolition impracticable. The hospitable law passed in the time of Richard, Duke of York, against the arrest of refugees by virtue of writs issued in England, was repealed. The English acts, against provisors to Rome—ecclesiastics who applied for or accepted preferment directly from Rome—were adopted. It was also enacted that all offices should be held at the King's pleasure; that the Lords of Parliament should appear in their robes as the Lords did in England; that no one should presume to make peace or war except with license of the Governor; that no great guns should be kept in the fortresses except by similar license; and that men of English birth only should be appointed Constables of the Castles of Dublin, Trim, Leixlip, Athlone, Wicklow, Greencastle, Carlingford, and Carrickfergus. But the most important measure of all was one which provided that thereafter no legislation whatever should be proceeded with in Ireland, unless the bills to be proposed were first submitted to the King and Council in England, and were returned, certified under the great seal of the realm. This is what is usually and specially called in our Parliamentary history "Poyning's Act," and next to the Statute of Kilkenny, it may be considered the most important enactment ever passed at any Parliament of the English settlers.

The liberation of the Earl of Kildare from the Tower, and his restoration as Deputy, seems to have been hastened by the movements of Perkin Warbeck, and by the visit of Hugh Roe O'Donnell to James IV., King of Scotland. O'Donnell had arrived at Ayr in the month of August, 1495, a few weeks after Warbeck had reached that court. He was received with great splendour and cordiality by the accomplished Prince, then lately come of age, and filled with projects natural to his youth and temperament. With O'Donnell, according to the Four Masters, he formed a league, by which they bound themselves "mutually to assist each other in all their exigencies." The knowledge of this alliance, and of Warbeck's favour at the Scottish Court, no doubt decided Henry to avail himself, if possible, of the assistance of his most powerful Irish subject. There was, moreover, another influence at work. The first countess had died soon after her husband's arrest, and he now married, in England, Elizabeth St. John, cousin to the King. Fortified in his allegiance and court favour by this alliance, he returned in triumph to Dublin, where he was welcomed with enthusiasm.

In his subsequent conduct as Lord Deputy, an office which he continued to hold till his death in 1513, this powerful nobleman seems to have steadily upheld the English interest, which was now in harmony with his own. Having driven off Warbeck in his last visit to Ireland (1497), he received extensive estates in England, as a reward for his zeal, and after the victory of Knock-doe (1505), he was installed by proxy at Windsor as Knight of the Garter. This long-continued reign—for such in truth it may be called—left him without a rival in his latter years. He marched to whatever end of the island he would, pulling down and setting up chiefs and castles; his garrisons were to be found from Belfast to Cork, and along the valley of the Shannon, from Athleague to Limerick.