The winter of 1799–1800 was marked by fierce discontent; and again, after the rise of Bonaparte to power, there were rumours of invasion which excited the peasants of South Ireland. The men of Dublin on some occasions assaulted Unionist Members of Parliament. Cornwallis, however, believed that the country as a whole favoured the cause; and Castlereagh received favourable assurances as to the attitude of the great majority of Catholics except in County Dublin.[568] Some leading Episcopalians were appeased by the insertion of a clause uniting the Protestant Churches of England and Ireland in one body. This concession did not satisfy the Orangemen, who, despite the prohibition of their Grand Lodge, clamoured against the Union, and threatened to oppose it by force.

So doubtful were the omens when Cornwallis opened the Irish Parliament on 5th February 1800, in a speech commending the present plan of unification. Castlereagh then defended the proposals and declared them to have the support of three fourths of the property there represented. After showing the need of keeping the debts of the two islands distinct, he explained that an examination of the Customs and Excise duties warranted the inference that the contribution of Ireland towards Imperial expenses should be two fifteenths of that of Great Britain. He claimed that this plan would press less heavily on Ireland than the present duty of contributing £1,000,000 to the British armaments in time of war and half that amount in peace. Further, the Union would tend to assuage religious jealousies and to consolidate the strength of the Empire. Early on the next morning the House divided—158 for and 115 against Government. This result did not wholly please Dublin Castle. Cooke wrote on the morrow to Auckland: "The activity and intimidation of Opposition, together with their subscription purse, does sad mischief. They scruple not to give from 3,000 to 4,000 guineas for a vote." Government therefore had to mourn over seven deserters.[569] Nevertheless, this division was decisive. Castlereagh rounded up his flock, and by the display of fat pasture called in some of the wanderers. Is it possible that the Opposition purse was merely the device of a skilful auctioneer, who sends in a friend to raise the bids?

The triumph of Government at Dublin had its effects at Westminster. On 21st April 1800 Pitt explained the Resolutions as recently accepted by the Irish Parliament. He spoke very briefly, probably owing to ill health, which beset him through many weeks of that year.[570] He soon met a challenger. Thomas Jones dared him to combat by accusing Ministers of seeking to disfranchise Ireland by corrupt means. Foiled in argument, they now acted on the principle

Flectere si nequeo superos, Acheronta movebo.

After a further display of classical knowledge, Jones declared that the introduction of 100 Irish members into that House must destroy the British constitution, which, like Damocles, would for ever be threatened with the sword of Dionysius suspended over it by a single hair.

Disregarding rhetoric and classical allusions, Pitt plunged into business. In none of his speeches is there a simpler statement of a case. He declared the Union to be absolutely necessary as a means of thwarting the machinations of an enemy ever intent on separating the two kingdoms. It would further allay the religious animosities rife in Ireland, and would conduce to her freedom and happiness. He then uttered these words: "It may be proper to leave to Parliament an opportunity of considering what may be fit to be done for His Majesty's Catholic subjects, without seeking at present any rule to govern the Protestant Establishment or to make any provision upon that subject." This statement is not wholly clear; but it and its context undoubtedly opened up a prospect of Catholic Emancipation such as Cornwallis had far more clearly outlined. The significance of Pitt's declaration will appear in the sequel.

On the subject of commerce Pitt laid down the guiding principle that after the Union all Customs barriers between the two islands ought to be swept away as completely as between England and Scotland. If at present they swerved from this grand object, it was for the sake of reaching it the more surely. In compliance with the demand of Ireland, they would allow her to maintain a protective duty of 10 per cent. on cottons and woollens, in the latter case for not more than twenty years. He then added these words: "The manufacturers of this country do not, I believe, wish for any protecting duties; all they desire is a free intercourse with all the world; and, though the want of protecting duties may occasion partial loss, they think that amply compensated by general advantage." No more statesmanlike utterance had been heard in the House of Commons. Only by degrees had Pitt worked his way to this conviction. In his early Budgets, as we saw, he clung to the system of numerous duties; but, despite the cramping influence of war, he now relied on the effects of a two-shilling Income Tax and aimed at the abolition of protective Customs dues. He was fated never to reach this ideal; but there can be no doubt that he cherished it as one of the hopes of his life.

Turning next to the question of Ireland's contribution to the Imperial Exchequer, Pitt set forth his reasons for fixing it at two fifteenths of the revenue of Great Britain; but, as this decision might in the future unduly burden the smaller island, it would not be final; and he suggested that at the end of twenty years the resources of each would so far have developed as to admit of a more authoritative assessment. If, however, in the meantime the amount paid by Ireland should be in excess of what ought to be paid, the surplus should be applied either to the extinction of her Debt or to local improvements. He further expressed the hope that in course of time the Debts and the produce of taxation would be so far assimilated in the two kingdoms as to admit of the formation of one National Debt and one system of taxation. Despite the favourable nature of these proposals, Pitt encountered a spirited opposition. Grey declared the measure to be a gross violation of the rights of the Irish people. Sheridan, Dr. Laurence (the friend of Burke), and Tierney continued in the same strain; and Grey finally dared the Minister to dissolve the Irish Parliament and appeal to the people. Throwing off all signs of bodily weakness, Pitt took up the challenge. Last year, he said, when the Commons of Ireland rejected the Union, certain members applauded them. Now, when they passed it, the same members said "appeal to the people." He refused to do so, knowing well the scenes of violence and intimidation that would result from consulting primary assemblies of Irishmen. The reference to those bodies, so notorious during the French Revolution, clinched his reply; and the House expressed approval of the Union by 236 votes to 30 (21st April 1800).

The further debates on the Bill are of little interest. In the absence of Fox, Grey was the protagonist of Opposition. Bankes, once a firm supporter of Pitt, opposed the measure. Wilberforce confessed to tremulous uncertainty about it, ostensibly because the addition of 100 Irish members to the House would add to the influence of the Crown, but more probably because he foresaw Catholic Emancipation. Peel, already known as one of the most successful and patriotic of Lancashire manufacturers, spoke up manfully for the Union, though he deeply regretted that Ireland would retain certain protective duties against Great Britain. Very noteworthy, in view of the son's championship of Free Trade in 1845, was the contention of the father that a weak country (Ireland) had no need of "protection" against a stronger one. In reality it would be as if a poor family shut its doors against assistance from a wealthy one. On the trading proposals Pitt's following was thinned down to 133; but the main question went through in May by overwhelming majorities in both Houses. In the following month it passed through the Irish Parliament.

Castlereagh thereupon introduced a Bill to indemnify the holders of pocket boroughs who would lose patronage by the proposed changes. The Government, having now revised its previous resolve, proposed to disfranchise as many as 84 small Irish boroughs, and allotted £15,000 for each, or £1,260,000 in all. In explanation of this payment it must be remembered that the owning of such boroughs was a recognized form of property, as appeared in Pitt's proposal of 1785 to compensate British owners whom he sought to dispossess. Nothing but the near approach of revolution in 1832 availed to shatter the system of pocket boroughs in Great Britain; and then their owners were sent empty away. The difference in treatment marks the infiltration of new ideas. In England and Ireland a vote and a seat had been a form of property. According to the Rights of Man the franchise was an inalienable right of citizenship.