He was Speaker of the Irish House of Commons in the Parliament of 1585–86 and a close ally of the Lord Deputy of Ireland, Sir John Perrot.
Perrot's downfall did some short-term damage to Walsh's career, but he soon regained his influence, as he was noted for his loyalty to the English Crown, and enjoyed the Queen's personal regard.
[2] He took some interest in traditional Gaelic culture: the well-known Irish poem, Labhrann ar Iongaibh Éireann, by Tuileagna Ó Maoil Chonaire, was addressed to him.
His sister Johanna married another protégé of the Earl of Ormond, Gerald Comerford, who like Nicholas went on to become a trusted Crown official and a High Court judge, but died, still a relatively young man, in 1604.
He was promoted to the position of second justice of the Court of King's Bench, and when Perrot called the last of the three Elizabethan Irish Parliaments in 1585, Walsh sat in the House of Commons as member for Waterford.
He was also elected Speaker of the House, and in May 1586 delivered a lengthy oration at the prorogation of the parliament, in which he praised the virtues of monarchy, while deploying the difficulties caused by the Queen's remoteness from Ireland.
He rebuked Parliament for failing to vote the taxes required by the Crown, while maintaining that all three estates in society – monarchy, aristocracy, and democracy – had a right to a voice in government.
[1] Due to the friendship of Fitzwilliam, who wished to retain his services, and the support of Burghley, he escaped prosecution and soon regained his political influence.
Sarsfield was pardoned after making a full submission, but Meade remained defiant and the Crown, unwisely as it turned out, set up a special Court to try him for treason.
[8] The result was a fiasco since the jury, despite being composed largely of Protestants of undoubted loyalty to the Crown, insisted, despite strenuous efforts to coerce them to convict, on bringing in a verdict of not guilty.
There is a story, originating with David Rothe, Bishop of Ossory, that Walsh converted to Roman Catholicism on his deathbed, and that his funeral was conducted according to the Catholic ritual, much to the embarrassment of the Crown which he had served so loyally.
On the outbreak of the Irish Rebellion of 1641, Sir Nicholas Walsh the younger (of Piltown and Ballykeroge) became one of the leaders of Confederate Ireland and died fighting to protect his property from the threatened English plantation.
However, recent research shows that at least one lesser cadet branch, the Walshes (or Welshes) of Canty and Woodstock, County Waterford, continued in occupation of Piltown lands into the late 19th century.
Tuileagna Ó Maoil Chonaire addressed to Sir Nicholas Walsh his poem Labhrann ar iongaibh Éireann.
This related the true story of a judgment given in the eighth century by Niall Frossach, King of Aileach, concerning a mother and her fatherless child.
The choice of Walsh as the addressee of the poem suggests that he not only spoke Irish[15] but had some interest in Gaelic culture, perhaps fulfilling the traditional role of "patron".