The restaurant was opened by brothers John and Peter Delmonico from Ticino , Switzerland . In 1831, they partnered with their nephew Lorenzo Delmonico, who became responsible for the restaurant's wine list and menu design. In 1862, the restaurant hired Charles Ranhofer , who was considered one of the finest chefs of the time. During the early 1850s, the restaurant hosted the New England Society of New York, a society that hosted some of the greatest orators of the day. In 1860, Delmonico's catered Edward VII 's Grand Ball at the Academy of Music on 14th Street. For some years it was associated with the most popular meals of the time, and its menus are used today as sources for historical research into contemporary culinary tastes.
The restaurant was very successful from 1865 to 1888 and expanded its brand with other restaurants of the same name. In 1919, Edward L.C. Robins purchased Delmonico's Restaurant. His grand establishment, called "The Citadel," on Fifth Avenue and 44th Street, closed in 1923.