In January, 1535, seven hundred men were sent from Dublin to burn Maynooth Castle. A skirmish took place, and although some of the rebels were slain, the royal troops retired.
The Lord Deputy, Sir William Skeffington, now collected his forces, and marched in full strength against the stronghold. The siege began on the 14th of March, and was continued until the 23rd.
Upon arriving at Maynooth, Sir William demanded the surrender of the castle, and offered free pardon and reward to all the garrison.
To this he only received a jeering reply, so planting his cannon to the north of the building towards the park he opened fire. The attack was varied north-east and north-west, but though this continued for over a week little damage was done, save destroying the battlements.
Towards the close of this time a letter was shot out of the castle to the Lord Deputy from Christopher Paris, offering to find means of letting the besiegers enter the castle for a certain sum of money and provision for the rest of his life.
Sir William Skeffington agreed to the terms, and upon the 22nd, a field-piece having been captured from the besiegers, the Governor made it an occasion for high revelry. Thus, while the men who guarded the outer battlements were sound asleep after their carouse, the King’s troops easily entered the castle by scaling-ladders early on the morning of the 23rd.
Sir William Brereton led the attack, but the resistance was very feeble, the drunken soldiers believing that the cry of “St. George! St. George!” was but a dream. Sir William hoisted his standard from the highest turret, so as to inform the Lord Deputy that the castle had been won.
Sir William Skeffington entered in the afternoon. The garrison consisted of thirty-seven persons. Two singers of the chapel were pardoned, at the intervention of Chief Justice Aylmer, on account of their sweet voices.
Twenty-five of the men were beheaded, and one hanged, outside the castle gate, and the principal heads placed upon the battlements. Amongst these was that of the Dean of Kildare. Paris was paid the sum stipulated for his treachery, but as he had forgotten to make his safety a condition, he was executed with the rest.
The Lord Deputy left a garrison in the castle and returned to Dublin.