Sir William FitzGerald, the then Lord Deputy, complained loudly of the extraordinary powers granted to Essex; and some show of deference to his authority was made by requiring the Earl to receive his commission from him.  Essex landed in Ireland in 1573, and the usual career of tyranny and treachery was enacted.  The native chieftains resisted the invasion of their territories, and endeavoured to drive out the men whom they could only consider as robbers.  The invaders, when they could not conquer, stooped to acts of treachery.  Essex soon found that the conquest of Ulster was not quite so easy a task as he had anticipated.  Many of the adventurers who had assumed his livery, and joined his followers, deserted him; and Brian O’Neill, Hugh O’Neill, and Turlough O’Neill rose up against him.  Essex then invited Conn O’Donnell to his camp; but, as soon as he secured him, he seized his Castle of Lifford, and sent the unfortunate chieftain a prisoner to Dublin.

In 1574 the Earl and Brian O’Neill made peace.  A feast was prepared by the latter, to which Essex and his principal followers were invited; but after this entertainment had lasted for three days and nights, “as they were agreeably drinking and making merry, Brian, his brother, and his wife were seized upon by the Earl, and all his people put unsparingly to the sword-men, women, youths, and maidens—­in Brian’s own presence.  Brian was afterwards sent to Dublin, together with his wife and brother, where they were cut in quarters.  Such was the end of their feast.  This wicked and treacherous murder of the lord of the race of Hugh Boy O’Neill, the head and the senior of the race of Eoghan, son of Nial of the Nine Hostages, and of all the Gaels, a few only excepted, was a sufficient cause of hatred and dispute to the English by the Irish."[437]

Essex visited England in 1575, and tried to induce the Queen to give him further assistance in his enterprise.  On her refusal, he retired to Ireland, and died in Dublin, on the 22nd September, 1576.  It was rumoured he had died of poison, and that the poison was administered at the desire of the Earl of Leicester, who soon after divorced his own wife, and married the widow of his late rival Essex complained bitterly, in his letter to Sir Henry Sidney, of the way in which he had been treated in his projected plantation of Clannaboy, and protested against the injustice which had been done through him on O’Donnell, MacMahon, and others, who were always peaceable and loyal, but “whom he had, on the pledged word of the Queen, undone with fair promises.”  Probably, only for his own “undoing,” he would have had but scant pity for others.