He had meanwhile been joined by his young wife and infant daughter. His prospects during these months were exceedingly problematical. In 1850, however, he removed to Boston and began to publish the American Celt, a paper which was of precisely the same cast as the defunct New York Nation had been. It was full to the brim of hatred and rancour against Great Britain, and its "mission" seemed to be to influence all the evil passions of the Irish race in America. By degrees, however, Thomas D'Arcy McGee began to feel the influence of the civilized atmosphere in which his life was passing. He figured conspicuously on the lecture platform, and was necessarily brought into contact with men of good intellect and high principles. These persons felt and expressed respect for his abilities, but declined to sympathize with, or even to discuss, the merits of English rule in Ireland. They tacitly refused to consider that subject as an absorbing theme for discussion on this continent. He received much wise counsel, the tenor of which led him, for the first time in his life, to reflect seriously upon the errors of his past career. He was apt enough to learn, and gradually the idea began to dawn upon his mind that all the wisdom and justice in the world are not confined to Irish bosoms. He began to perceive that there are nobler passions in the human heart than revenge, and that if a man cannot make circumstances conformable to his mind, the first thing in his power is to conform his mind to his circumstances. "The cant of faction," says Mrs. Sadlier, "the fiery denunciations that, after all, amounted to nothing, he began to see in their true colours; and with his whole heart he then and ever after aspired to elevate the Irish people, not by impracticable Utopian schemes of revolution, but by teaching them to make the best of the hard fate that made them the subjects of a foreign power differing from them in race and in religion; to cultivate among them the arts of peace, and to raise themselves, by the ways of peaceful industry and increasing enlightenment, to the level even of the more prosperous sister-island."

This radical change of opinion was not brought about in a day, nor in a year. The progress of the mental revolution was slow, but certain, and by degrees the past of Thomas D'Arcy McGee stood revealed to him in all its insufficient barrenness. He fought against his steadily-strengthening convictions as long as he could, but his judgment and good sense at last won the day. In the month of August, 1852, he liberated his mind in a letter published in the Celt, and addressed to his friend Thomas Francis Meagher. In that letter he unfolded with much frankness the process by which he had been led to modify his opinions, and referred to the scheme of the past as "the recent conspiracy against the peace and existence of Christendom." His emancipation was complete, and from this time forward there was an entire revolution in the tone of all his writings and public speeches. Instead of writing diatribes against the irrevocable he adopted "Peace and good will among men" as his motto. Amicable relations were restored between him and the Roman Catholic hierarchy, and erelong, at the request of the late Bishop Timon, of Buffalo, he removed the office of publication of the Celt to that place. He continued the publication for about five years after the removal, during which time he made many friends and achieved a fair share of worldly prosperity. He was a diligent, albeit rather a fitful student, and amassed a considerable fund of political and general knowledge. His paper was regarded as the chief exponent of Irish Catholic opinion on this continent, and as a standard authority on all matters connected with Irish affairs. Some of his ablest lectures were composed and delivered during this period, and some of them were the means of greatly extending his reputation. Among those which evoked the most flattering criticism from the press, those on "The Catholic History of America," "The Irish Reformation," and "The Jesuits" occupy the foremost place. The many demands upon his time did not prevent him from engaging in various laudable enterprises for ameliorating the moral and social condition of his countrymen in America, and from putting forth many valuable suggestions for their guidance. It was his special object, says one of the most sympathetic of his critics, to keep them bound together by the memories of their common past, and to teach them that manly self-respect which would elevate them before their fellow-citizens, and keep them from political degradation. He strove to make them good citizens of their adopted country, lovers of the old cradle-land of their race, and devoted adherents of what to them was "the sacred cause of Catholicity." Among other schemes vigorously propounded by him for their material advancement was that of colonization—"spreading abroad and taking possession of the land; making homes on the broad prairies of the all-welcoming West," instead of herding together in the tenement houses of the large cities. In furtherance of this project he organized a Convention at Buffalo at which he addressed the assembled representatives with great eloquence. He began, however, to experience the pecuniary difficulties inseparable from the conduct of a newspaper which declines to ally itself with any political party, for he had persistently held aloof from the troubled sea of party-politics in the United States. These difficulties increased, and were sometimes so great as to occasion serious embarrassment. His future prospects were not bright, and he looked forward with some anxiety. When matters had reached a pretty low ebb with him he was advised to change his base of operations. His journalistic pursuits and his platform experiences had brought him into contact with many prominent Irish Canadians, with some of whom he had formed warm personal friendships. By these gentlemen he was urged to take up his abode in Montreal, where, as he was informed, the want of a ruling mind such as his was sensibly felt by the rapidly-increasing Irish population. It was further represented to him that the appreciation he had met with in the United States had been by no means commensurate with his deserts, and that his compatriots in Canada stood in urgent need of his services. To such representations he was not disposed to turn a deaf ear, more especially as the pecuniary outlook in Buffalo was far from encouraging. After careful deliberation he assented to the proposal which had been made to him, disposed of his interest in his newspaper, and removed to Montreal with his family early in 1857.

The manner of his reception in Montreal was such as could not fail to be highly gratifying to his feelings. His fellow-countrymen vied with each other in doing him honour, and in affording him material support. He established a newspaper called the New Era. His acquaintance with Canadian affairs at this date was not very wide, and he was compelled to take a somewhat non-committal stand on many questions which the public had at heart. On one subject, however, he spoke with no uncertain sound. He advocated with great energy and eloquence the scheme of an early union of the various British colonies in North America. The New Era did not realize, in a pecuniary sense, the expectations of its founder, but as matters turned out, its success or non-success was a matter of little importance. At the next general election Mr. McGee, after a close contest, was returned to Parliament as the representative of Montreal West. The publication of the newspaper was discontinued, and he devoted himself to his duties as a legislator.

From the time of first taking his seat in Parliament he was a conspicuous figure there; but it must be confessed that during the earlier sessions of his Parliamentary career he did little to inspire the public with any belief in his profound statesmanship. He arrayed himself on the side of the Opposition, and attacked the then-existing Cartier-Macdonald Administration with all the fiery eloquence at his command. "It was observed," says Mr. Fennings Taylor, "that he was a relentless quiz, an adroit master of satire, and the most active of partisan sharpshooters. Many severe, some ridiculous, and not a few savage things were said by him. Thus from his affluent treasury of caustic and bitter irony he contributed not a little to the personal and Parliamentary embarrassments of those times. Many of the speeches of that period we would rather forget than remember. Some were not complimentary to the body to which they were addressed, and some of them were not creditable to the person by whom they were delivered. It is true that such speeches secured crowded galleries, for they were sure to be either breezy or ticklish, gusty with rage, or grinning with jests. They were therefore the raw materials out of which mirth is manufactured, and consequently they ruffled tempers that were remarkable for placidity, and provoked irrepressible laughter in men who were regarded as too grave to be jocose. Of course they were little calculated to elicit truth, or promote order, or attract respect to the speaker. Mr. McGee appeared chiefly to occupy himself in saying unpleasant and severe things; in irritating the smoothest natures, and in brushing everybody's hair the wrong way." The personalities in which he permitted himself to indulge were frequently in the worst conceivable taste, and he raised up for himself many enemies. It began to be suspected that this brilliant Irishman, whose advent into Canadian political life had been heralded with so loud a flourish of trumpets, was no heaven-born statesman, after all. He said some clever things in the course of his speeches, and a good many other things that were neither clever nor sensible. There was an evident desire on his part to attract attention to himself, and his self-consciousness was sometimes so marked as to be positively offensive. It was difficult to say why he had joined the ranks of the Opposition. Of the local politics he, at the time of his entry into Parliament, knew little or nothing, and there was not much in common between him and the leaders of the Party to which he had attached himself. The latter could not feel as though their ranks had been very powerfully strengthened by such an accession. As the years passed by, however, D'Arcy McGee became more tractable, and—be it said—more sensible. He never entirely overcame his fondness for displaying his Irish wit on the floor of the House, but he taught himself to be more amenable to certain rules of debate which are tacitly recognized among the members of all grave deliberative assemblies. To put the matter in plain English, he less frequently transgressed the bounds of decorum and sober good-breeding. With increase of years came increase of knowledge as to the needs of the country, and as to the proper functions of a legislator. His intellectual vision became keener, and his views acquired breadth. It began to be apparent that there was a serious side to his character, and that he could rise to a high level upon a great occasion. No one had ever doubted that he possessed a goodly share of genius, but he began to show that he also possessed more practical qualifications for a statesman. Though largely endowed with the poetical temperament, he did not disdain to interest himself in such prosaic matters as statistics, and could make an effective speech of which figures formed the main argument. His oratory, though florid and discursive, began to exhibit symptoms of a genuine manly purpose. He studied law, and in 1861 was called to the Bar of the Lower Province, though he never seriously devoted himself to the practice of that profession. He continued to fight in the Opposition ranks until the downfall of the Cartier-Macdonald Ministry in the month of May, 1862. In the Administration which succeeded, under the leadership of John Sandfield Macdonald and Louis Victor Sicotte, he accepted office as President of the Council. After the resignation of the Hon. A. A. Dorion, he also acted for some time as Provincial Secretary. Upon the reconstruction of the Administration in the following year he was not invited to take a portfolio, and his dissatisfaction at the cavalier treatment to which he had been subjected soon began to make itself apparent. He crossed the House, and voted against the new Government, accompanying his votes with remarks the reverse of complimentary to the Premier. Upon the formation of the Taché-Macdonald Government, which was nothing if not Conservative, in March, 1864, Mr. McGee became Minister of Agriculture; a position which he continued to hold until the accomplishment of Confederation. He had thus completely changed sides, though it does not appear that his party convictions had undergone any material modification, and it was alleged, with some show of truth, that he was actuated more by pique than by principle.

In the proceedings which resulted in Confederation Mr. McGee took a conspicuous and an honourable part. The union of the British North American Provinces, as we have seen, had been advocated by him from the time of his first arrival in the country. Independently of his speeches in the House, which were among the most brilliant efforts evoked by the occasion, he did good service by his writings in the public press, and by lectures and addresses delivered by him in various parts of Canada and the Maritime Provinces. In order that he might be relieved from pecuniary cares by which he was sometimes beset, his friends throughout the country organized a fund on his behalf, and purchased and presented him with a comfortable, well-appointed homestead in Montmorenci Terrace, St. Catherine Street, Montreal, wherein he and his family found a resting-place during the remaining years of his life. He was thus enabled to address himself to his cherished projects with comparative freedom from anxiety.

In 1865 he repaired to England as a Member of the Executive Council to confer with the Imperial Government upon the great question of Confederation. During his absence he, after an interval of seventeen years, once more set foot on his native land, and paid a visit to Wexford, the home of his boyhood, where he was the guest of his father. During his sojourn at Wexford on this occasion he delivered an eloquent speech on the condition of the Irish race in America. He publicly deplored the part he had played in the troubles of 1848, and enlarged upon the demoralized condition of his countrymen in the United States as compared with those resident in Canada. He proclaimed his conviction that the time for fruitless attempts at insurrection was past, and that he for his part should regard traitors to Great Britain as the enemies of human progress. This deliverance gave grievous offence to the Irish citizens of the United States, by many of whom D'Arcy McGee was thenceforward denounced as a renegade to his principles. This sentiment was strengthened by McGee's righteous denunciations of the Fenian horde who menaced our shores in the summer of 1866, and who shed the blood of some of our promising young men. At the general election of 1867 these utterances were called into requisition as an election cry. Mr. McGee had not accepted a portfolio in the first Government under Confederation, which had just been formed, but had waived his claim to office in favour of another Irish Catholic, Mr. Kenny, of Nova Scotia. McGee, however, though he was thus complaisant, had no intention of retiring immediately from public life, and once more offered himself to his constituents in Montreal West. That constituency was the abode of the local "Head Centre" of the Fenian Brotherhood, and the Fenian influence there was considerable. Mr. McGee's utterances had made him the object of the inveterate hatred of that body, and it was determined that he should be ousted from the seat which he had held ever since his entry into political life in Canada. Mr. Devlin, an Irish Catholic, and a prominent member of the Montreal Bar, was brought out as an opposition candidate, and the most shameless devices were resorted to to secure that gentleman's return. "Every vile epithet calculated to rouse ignorant Irish Catholics,"—says the author of "The Irishman in Canada,"—"was hurled at McGee. He had, as his manner was, gone right round from denying the existence of Fenianism in Montreal, to exaggerating the extent of it, and denouncing it, not in undeserved terms, but in terms which seemed violent from a man of his past history. He won his election, but by a majority which convinced him that his power had greatly waned. He had, however, the consolation that if he had lost popularity, he had lost it in enlightening his countrymen." He had felt it to be his duty to place Fenianism in its proper light before his fellow-countrymen in Canada. He knew that the order was powerless for good, and that it would entail pecuniary loss, if not absolute ruin, upon many well-meaning but ignorant and misguided persons. So far as the Fenian scheme contemplated an invasion of Canada, he regarded it with all the scorn and abhorrence of a loyal subject. For this he was denounced by the Fenians, and held up to execration as one who had sold himself to the spoiler.

Before the opening of the first session of the Dominion Parliament he was attacked by a long and severe illness, which brought him to death's door, and from which he only recovered in time to attend at the opening of the session. It was noticed that there was a decided change, not merely in his physical appearance, but in the workings of his mind. He had formerly been addicted to frequent indulgence in strong drink. He had now become rigidly abstemious and regular in all his habits. He seemed to be pervaded by a seriousness which almost amounted to melancholy. His friends believed these characteristics to be something deeper than the temporary humours of convalescence. His serious indisposition had made him reflect, and his situation was one which afforded ample food for reflection. Ever since the delivery of the Wexford speech he had been in receipt of frequent anonymous letters in which he was anathematized as a traitor, and warned to prepare for death. Some of these came from Ireland. The envelopes of a few of them afforded evidence of their having been posted in Montreal; but by far the greater number came from the United States. He affected to console himself with the proverb that "threatened men live long," but he could not bring himself to regard these truly fiendish communications with indifference. He knew the desperate character of the class of Irishmen from whom they emanated, and he shuddered as he reflected that he had at one time been the idol and fellow-worker of such as they. The shadow of his impending doom was upon him. During the interval between rising from his bed of sickness and the opening of the session in November he had determined to retire from public life in the course of the following year, and to devote the rest of his days to literary pursuits. His determination was not destined to be carried out. He took a part in the debates while the session was in progress, and some of the most statesmanlike utterances that ever passed his lips were delivered during this, the last winter he was ever to see. On the evening of the 6th of April he occupied his usual place in the House, and made a brilliant and effective speech on the subject of the lately-formed Union. A little after two o'clock on the following morning he left the House in company with two of his political friends, and proceeded in the direction of the place where he lodged—the Toronto House, on Sparks Street, kept by a Mrs. Trotter. When the three had arrived within a hundred yards of Mr. McGee's destination they separated, each betaking himself to his own lodging-house. Mr. McGee, having reached his door and inserted his latch-key, was just about entering, when the sound of a pistol-shot was heard by his landlady, who was awaiting his arrival. She hurried to the door, and opened it, to find Mr. McGee's body lying prone across the sidewalk. The alarm was given, and a crowd soon collected on the spot. The body was raised, but the assassin's bullet had done its work. The ball had entered the back of the head and passed through the mouth, shattering the front teeth, and producing what must have been instant and painless death.

The miscreant at whose hands D'Arcy McGee met his fate was a Fenian named Patrick James Whalen. He was subsequently arrested, tried, found guilty, and hanged at Ottawa.

Had Mr. McGee lived another week he would have completed his forty-third year; so that he was still a young man, and had his life been spared there is good reason to believe that he would have made an abiding mark in literature. During his lifetime he published many volumes, but they were for the most part written under disadvantageous circumstances, and merely afford indications of what he might have achieved in literature. His poems have been collected in various editions; but the work by which he is best known is his "Popular History of Ireland," originally published in two volumes at New York in 1863, and since reprinted in various forms.