O’Neill and O’Donnell may be justly considered the last of the independent native chieftains.  When the latter died in exile, and the former accepted the coronet of an English earl, the glories of the olden days of princes, who held almost regal power, had passed away for ever.  The proud title of “the O’Neill” became extinct; his country was made shire ground; he accepted patents, and held his broad acres “in fee;” sheriffs were admitted; judges made circuits; king’s commissioners took careful note of place, person, and property; and such a system of espionage was established, that Davies boasts, “it was not only known how people lived and what they do, but it is foreseen what they purpose and intend to do;” which latter species of clairvoyance seems to have been largely practised by those who were waiting until all suspicions were lulled to rest, that they might seize on the property, and imprison the persons of those whose estates they coveted.

In May, 1603, O’Neill had visited London, in company with Mountjoy and Rory O’Donnell.  The northern chieftains were graciously received; and it was on this occasion that O’Neill renounced his ancient name for his new titles.  O’Donnell was made Earl of Tyrconnel at the same time.  The first sheriffs appointed for Ulster were Sir Edward Pelham and Sir John Davies.  The latter has left it on record, as his deliberate opinion, after many years’ experience, “that there is no nation of people under the sun that doth love equal and indifferent justice better than the Irish, or will rest better satisfied with the execution thereof, although it be against themselves, so that they may have the protection and benefits of the law, when, upon just cause, they do desire it."

A plot was now got up to entrap O’Neill and O’Donnell.  Their complicity in it has long been questioned, though Dr. O’Donovan appears to think that Moore has almost decided the question against them.  Moore’s evidence, however, is hardly complete, while there is unquestionable authority which favours the opinion that “artful Cecil” was intriguing to accomplish their destruction.  Curry says, in his Historical Review:  “The great possessions of these two devoted Irish princes, proved the cause of their ruin.  After the successful issue of the plot-contriving Cecil’s gunpowder adventure in England, he turned his inventive thoughts towards this country.  A plot to implicate the great northern chieftains was soon set on foot, and finally proved successful.  The conspiracy is thus related by a learned English divine, Dr. Anderson, in his Royal Genealogies, printed in London, 1736:  ’Artful Cecil employed one St. Lawrence to entrap the Earls of Tyrone and Tyrconnel, the Lord Delvin, and other Irish chiefs, into a sham plot, which had no evidence but his.’”

The next movement was to drop an anonymous letter at the door of the council-chamber, mentioning a design, as then in contemplation, for seizing the Castle of Dublin, and murdering the Lord Deputy.  No names were mentioned, but it was publicly stated that Government had information in their possession which fixed the guilt of the conspiracy on the Earl of Tyrone.  His flight, which took place immediately after, was naturally considered as an acknowledgment of his guilt.  It is more probable that the expatriation was prompted by his despair.