[3] It had been constructed by hoteliers Frank Bering and Ernie Byfield atop the former site of the Huck Brewing Company.

[3] Among the who held long-term residence in the hotel were Doris Day, Helen Hayes, Eunice Kennedy, and Lana Turner.

However, reportedly after an interaction with a small poodle had enchanted Byfield, he revoked this policy and began offering special treatment to the dogs of guests.

[4][6] For many decades, the hotel would be well known for the service it offered catering to the dogs of its guests, with a 1991 Chicago Tribune article reporting on that continued reputation.

Indicative of the hotel's popularity at the time with celebrities, the hotel had to decline a request by the film's star, Cary Grant, to stay in the penthouse suite (which he had stayed in weeks earlier when in Chicago to promote his film Indiscreet) because it was being used by Judy Garland (who was in town for concert performances).

[5] In October 2022, it was reported that Gaw Capital had hired the hotel real estate brokers RobertDouglas to sell the property.

RobertDouglas has marketed the property to buyers as having potential either as a continued hotel operation or as an opportunity for redevelopment for another purpose.

[12] After the 2017 closure of The Pump Room, Lettuce Entertain You Enterprises opened a new restaurant in the space named "Booth One".

[19] During their 1959 visit to Chicago, Elizabeth II and Prince Philip, Duke of Edinburgh dined at the hotel at a luncheon hosted by Governor William Stratton.

[22] Like the Ambassador East, the hotel was featured in the film North by Northwest, with its marble front desk used in a scene in which Cary Grant's character is questioned by a clerk.