In 1607, the Government was thrown into the greatest alarm by a letter found on the floor of the council-chamber in the castle, containing intimations of a conspiracy entered into by the Earls of Tyrone and Tyrconnell, and other northern chieftains, to seize the city and excite a general insurrection against the English government. Instant measures were employed to arrest the imputed leaders, several of whom were taken and executed, but the two Earls had sufficient notice of the designs against them to save themselves by flight; their immense estates were confiscated.
In 1613, a parliament was held in Dublin, after a lapse of 27 years: it was the first in which representatives were sent from all the counties, and is still more remarkable for a dispute respecting the election of a speaker between the Protestant and Roman Catholic parties, which terminated in the triumph of the former, and the secession of the latter from the House of Commons.
In 1614, a convocation was held here, which established the thirty-nine articles of religion; and a subsequent convocation, in 1634, adopted a body of canons for the regulation of the Established Church.
After a period of 40 years of uninterrupted tranquillity, both to the city and the nation, the prospect of its further continuance was destroyed by the discovery of a plot to seize the castle, on the 23rd of October, 1641, as the first movement of a general insurrection against the English Government.
- The plan was disclosed by an accomplice, on the evening before the day it was to have been put into execution, and thus frustrated as far as the city was concerned.
- So little had the occurrence of such an event been apprehended that, in the year before, a large portion of the city walls was allowed to fall to ruin. To aid in their repairs, and to meet the other urgent necessities of the state, the citizens were called upon by proclamation to send in their plate, on promise of repayment, an expedient which produced only £1200 towards the relief of the public exigencies.
- Next year the mayor was invited to the council, to confer on a project for raising £10,000, half in money and the remainder in provisions, to enable the king's army to take the field; but such was the poverty of the place, that the project was relinquished as impracticable.
On an alarm of an intended attack on Dublin, by the Irish forces of Owen Roe O'Nial and General Preston, in 1646, the Marquess of Ormonde, then lord-lieutenant, determined to strengthen the city by a line of outworks thrown up on its eastern side, between the castle and the college.
- On this occasion, the women set a remarkable example of public spirit, the Marchioness of Ormonde and other ladies placing themselves at their head, and the whole assisting in carrying baskets of earth to the lines. Famine, however, proved the city's best safeguard.
- The Marquess had caused the country to he laid waste, and the mills and bridges to be destroyed for several miles round, so that the besieging army, amounting to 10,000 foot and 1000 horse, was forced to retire without any attempt of importance.
- So confident was Ormonde now of his own strength, that he refused admission to commissioners sent by the English parliament with 1400 men, but the very next year he was compelled, by extreme necessity, to surrender the place to them, rather than suffer it to fall into the hands of the Irish; after which, Owen Roe O'Nial, being baffled in another attempt upon the city, revenged himself by ravaging the surrounding country with such fury that from one of the town steeples 200 fires were seen blazing at once.
The Marquess of Ormonde returned in 1649, with a determination to regain possession of the city.
- He first fixed his headquarters at Finglas, but afterwards removed to Rathmines, on the south side.
- An unexpected sally of the garrison, to destroy some works he was throwing up at Bagotsrath, led to a general engagement, in which his troops, struck with an unaccountable panic, gave way with such precipitation, that he had scarcely time to make his escape.
The city remained in the hands of the parliament during the remainder of the war. At the close of the same year, Oliver Cromwell landed here with a well-appointed army of 13,000 men: after remaining a short time to refresh his troops, and to arrange his affairs, he left it for Drogheda, which he took, and treated those by whom he was opposed with a degree of cruelty seldom paralleled in the annals of modern warfare.
In 1652, the war having been declared at an end, a high court of justice was erected in Dublin, for the trial of persons charged with murder and other atrocities not tolerated by the rules of war, by which, among many others of less note, Sir Phelim O'Nial, the first and principal leader of the insurrection in Ulster, was condemned and executed.
In 1659, a party of general officers, well inclined to the Restoration, surprised the castle, and having secured the parliamentary commissioners of Government, who resided there, declared for a free parliament; they then, upon the petition of the mayor and aldermen, summoned a convention, and though the castle was again surprised by Sir Hardress Waller, for the parliament, he was forced to surrender it, after a siege of five days, and Chas. II. was formally proclaimed. Charles, immediately after his restoration, rewarded the services of the citizens by the donation of a cap of maintenance, a golden collar of office, and a foot company to the mayor, and some years after, a pension of £500 was allowed him in lieu of the company.
In 1663, several discontented officers, among whom was the notorious Col. Blood, formed a plan to seize the castle, which was discovered by one of the accomplices.
About this period the city began to increase rapidly in extent, and in the number and elegance of its public buildings. The ground to the north of the river, formerly considered as a separate jurisdiction, under the name of Oxmantown, was connected with the city by four new bridges, and has since formed an integral part of it: it had hitherto been but a single parish, but was, some years after, in consequence of the increase of houses and inhabitants, subdivided into three. Numerous improvements were successively carried into effect, and the increase of population kept pace with them.
In 1688, King James visited Dublin, where he held a parliament, which passed acts to repeal the act of settlement, to attaint a number of Protestants, and to establish an enlarged system of national education. He also established a mint, in which a quantity of base metal was coined.
The year 1690 is marked by the decisive battle of the Boyne, after which James passed one night in Dublin Castle, during his precipitate retreat from the kingdom; in 1701, an equestrian statue of William III was erected on College Green, to commemorate that victory.
On King William's arrival, his first act was to repair in state to St. Patrick's cathedral, to return public thanks for the success which had crowned his arms. Previously to the battle of the Boyne, Sir Cloudesly Shovel, who commanded at sea for the latter monarch, took a frigate out of Dublin harbour, in which much of the plate and valuables of the Roman Catholic nobility and gentry had been embarked, under an apprehension of the event which so soon after decided the fate of their cause in Ireland.