In October 1970, building permission was granted to Ed François et Fils S.A. for Oddenino's Hotels to begin construction of the Royal Windsor Hotel, ideally located next to Brussels' Grand-Place, where it is said the Duke of Wellington once inspected his troops before departing for the Battle of Waterloo in 1815. The hotel officially opened its doors on 21 March 1973, under the management of Mr. Morgan Jeff David.

In 1980, Mr. Richard Chiu founded Warwick International Hotels and, just one year later, added the Royal Windsor Hotel Grand Place to the group's growing global portfolio.

The hotel quickly earned a reputation as one of Brussels' most elegant and sophisticated 4-star addresses, showcasing traditional British style with refined oriental accents. It featured 275 guest rooms and suites, multiple meeting spaces, the Michelin-starred Les 4 Seasons restaurant, the lively Waterloo piano bar, and the Duke of Wellington English-style pub. The legendary Crocodile Night Club, known for its vibrant atmosphere and its two namesake crocodiles, became one of the city's top nightlife destinations before the animals were rehomed at the zoo after outgrowing their aquarium.

Over the years, the hotel has hosted numerous internationally renowned guests, including Lady Gaga, The Bee Gees, Jay-Z, Richard Gere, Johnny Hallyday, and many heads of state. Through various renovations, the property has continued to evolve, most notably with the creation of the Grand-Place Suite, featuring a remarkable 150-square-metre terrace with panoramic views over Brussels.