The college motto, Comme je trouve, is French for 'As I find.' It comes from the coat of arms of the Butler family, the great Anglo-Norman dynasty whose Earls and Dukes of Ormond patronised the school for centuries. The motto is meant to encourage grit -- the idea of striving through adversity and taking life's challenges head-on, accepting circumstances as they are and finding a way through. Founded in 1538 by Piers Butler, 8th Earl of Ormond, and his wife Margaret, the school was originally called Kilkenny Grammar School and sat near St. Canice's Cathedral, replacing an even older institution: the School of the Vicars Choral, which had been founded in 1234. It is possible that no other educational institution in Ireland can claim a continuous teaching tradition stretching back as far.

The school closed for a stretch in the 1650s during the upheaval that followed the English Civil War's spillover into Ireland. It reopened as Kilkenny College in 1667 under James Butler, 1st Duke of Ormond, who continued the family tradition of patronising education. It soon became one of the most famous schools in Ireland. By the late 18th century a new college building stood on John Street overlooking the River Nore. At one point the institution was even termed a university and supported three professors. Then it collapsed almost completely: by the end of the 19th century there was a single pupil left. The college was saved only by amalgamation with the nearby Pococke School. In 1973 it merged with the Collegiate School Celbridge and became co-educational. In 1985 it relocated to a 63-acre campus at Celbridge House on the outskirts of Kilkenny.

The list of distinguished past pupils reads like an Anglo-Irish hall of fame. Jonathan Swift, the satirist who gave the world Gulliver's Travels and served as Dean of St. Patrick's Cathedral Dublin, was a student. George Berkeley became one of the most important British philosophers of the 18th century and Bishop of Cloyne, his name carried to a Californian university whose city now bears it. William Congreve and George Farquhar both shaped Restoration comedy. Abraham Colles became President of the Royal College of Surgeons in Ireland at 29 and twice declined a knighthood. The 1st Earl Beatty commanded the Grand Fleet. Maeve Kyle, born in 1928, became an Olympian and an Irish hockey international. Caroline Langrishe, the actress, is the niece of one alumnus -- the family connection through the Langrishe baronets of nearby Knocktopher ties the school into half of Kilkenny aristocracy.

In March 2013 Kilkenny College announced that it would no longer be charging tuition fees for all students, transferring effectively into the state-funded sector. Boarders and students taking part in extra-curricular activities still pay for those services, but the core schooling is free. The college remains the largest co-educational boarding school in Ireland, and the largest Church of Ireland school in the country, though it is open to all denominations. Its 50-acre campus is set among landscaped grounds outside the city, with classrooms and dormitories and dining facilities clustered together. Rugby and hockey are the dominant sports. In its almost 500 years, the school's character has shifted from grammar school to university, from boys' school to co-educational, from fee-paying to state-funded -- but the Butler motto over the door still reads Comme je trouve.