The castle began as a Norman stronghold, built on the perimeter of a monastic site by the House of Burke in 1228. The de Burgos held it for three and a half centuries before losing it to Sir Richard Bingham, Lord President of Connaught, in 1589. The Browne family received it in a Royal Grant around 1670 and built a hunting lodge in the style of a French chateau -- the double-headed eagles on the roof still represent their coat of arms. Then came the Guinness family. Sir Benjamin Guinness purchased the estate in 1852 through the Encumbered Estates Court, adding Victorian extensions. His son Arthur, 1st Baron Ardilaun, expanded further in the Neogothic style, creating the sprawling castle visible today.

Ashford's guest list reads like a century of celebrity. King George V and Queen Mary stayed here. John Lennon and George Harrison visited. Oscar Wilde spent much of his childhood on his father Sir William Wilde's adjacent estate. President Ronald Reagan came through, as did Prince Rainier of Monaco and Grace Kelly. Pierce Brosnan has been a guest. Golfer Rory McIlroy married Erica Stoll at the castle on 22 April 2017. The CW television series Reign used Ashford as its primary filming location for its 'French Court' set, with cast and crew returning annually for the first three seasons. Today, sixty percent of guests come from the United States, with Californians accounting for the largest share.

The castle's modern history has been as turbulent as its medieval past. Noel Huggard bought it in 1939. John Mulcahy purchased it in 1970, overseeing a complete restoration and doubling its size. A group of Irish-American investors including Chuck Feeney and Tony O'Reilly acquired it in 1985. In 2007, it sold for fifty million euros to Galway property investor Gerry Barrett -- just before the Irish financial crisis made such prices seem insane. The Bank of Scotland placed the property in receivership in November 2011, though the hotel continued operating. Staff accepted pay cuts of twenty to thirty percent to keep the doors open. A forty-seven-million-euro restoration followed: all 820 windows replaced, a new lead roof installed, stonework repointed. By 2015, Ashford Castle was voted the world's best hotel by Virtuoso Travel Week.

Ashford sits on the County Galway side of Lough Corrib, Ireland's largest lake, and its grounds sweep down to the water through manicured gardens and ancient woodland. From the air, the castle is unmistakable -- a sprawling Victorian Gothic complex of grey stone against the dark waters of the lough. But the relationship between castle and community has not always been smooth. In 2011, Gerry Barrett installed electric gates blocking a centuries-old public right of way over a bridge near the castle. When a letter requesting the road be reopened was ignored, 150 locals and elected officials protested. Barrett had attempted to block the protest with a High Court injunction. The incident is a reminder that in rural Ireland, the tension between private wealth and communal rights stretches back as far as the castle itself.