The Pump Room opened in the Ambassador East Hotel on October 1, 1938, and quickly became a celebrity magnet.  The roster of stars and power-brokers who dined there through the years is so extensive that it might be easier to create a list of people who did not eat there.  in the heyday, guests included humphrey bogart, lauren bacall, frank sinatra, judy garland, john f. kennedy, natalie wood, dustin hoffman, and robert redford.  but then the times "they were a-changing," and the customers included such rock 'n' roll icons as led zeppelin, david bowie, and the sex pistols.  the Celebrities and heavy hitters were famously and inevitably seated at "Booth One," which came with its own telephone.

The restaurant grew old gracefully, then drifted into senility like Irving Berlin.  In 2010, in the wake of a national financial crisis, the now-vintage hotel was acquired by Ian Schrager, New York City's perpetually uberhip purveyor of the next big thing.   The Pump Room was closed for extensive remodeling in January 2011, but reopened eight months later in completely new form, modeled after the ABC Kitchen in Manhattan, which won the James Beard Foundation's 2011 award for best new restaurant and whose chef, Jean-Georges Vongerichten, is no stranger to Chicago.  In the meantime, the Ambassador East officially became a thing-of-the-past.  It has now become the "Public Hotel Chicago," part of a newly-created hospitality concept.