For 53 years, Tommy Rowles asked “What are you having?” to the likes of Elizabeth Taylor, Paul McCartney and anyone else who bellied up to the bar he presided over.

Some of them ordered a Tommy Rowles; after he had worked there for a while, a rum-and-cognac concoction named for him was added to the drink menu.

The place was Bemelmans Bar, in the Carlyle hotel in Manhattan. Mr. Rowles, who worked there until he retired in 2012, died on Nov. 11 at age 78.

His daughter, Sharon Connelly, confirmed the death. She said Mr. Rowles had dementia.

On the job at Bemelmans Bar, known for its murals by the artist Ludwig Bemelmans and its little tables with their little lights, Mr. Rowles mixed and poured for the famous and the influential. But whatever secrets they imparted, he kept. His guiding principle was that what happened in Bemelmans stayed in Bemelmans.