St. Ermin’s stands on the site of a 15th-century chapel dedicated to St. Ermin (derived from St. Armel). By the mid to late 19th century, Westminster was undergoing rapid transformation, and in 1889 architect E. T. Hall created St. Ermin’s Mansions — the very building that forms the foundation of today’s hotel.
A decade later, in 1899, the mansion blocks were converted into a hotel. The new owners commissioned a major redesign of the interiors, led by celebrated Victorian theatre designer J. P. Briggs. His dramatic reception rooms, adorned with intricate plasterwork, became a defining feature of the building. A vintage marketing brochure from around 1910 captures this spectacular craftsmanship, much of which remains lovingly preserved today. Even then, St. Ermin’s embraced innovation: the brochure proudly notes that every bedroom had a telephone, replacing the traditional bell system to enhance the guest experience.