Claude Frollo
The process of preparing the final libretto was slow, and rehearsals for the opera did not begin until over three years after Hugo wrote the first lines. Bertin's requests for lines of various lengths to fit the music partly contributed to this as well as the task of condensing a long novel into a four-hour opera. Many of the characters were eliminated including Jehan Frollo, the dissolute younger brother of the chief antagonist Claude Frollo, although some aspects of his character were incorporated into Claude's. The main protagonist of the novel, Quasimodo, has a much reduced role in the opera, which concentrates more on the love story between Esmeralda and Phoebus. At Bertin's request, the ending of the novel was also changed with Esmeralda escaping execution. In 1834, "Notre-Dame de Paris" had been placed on the "Index Librorum Prohibitorum", the list of works condemned by the Catholic Church. The opera libretto was submitted to the censors in January 1836 who required the title to be changed to "La Esmeralda" and all references to Claude Frollo as a priest to be removed. (The printed libretto which was sold prior to the premiere did have the change of title but retained the use of "priest" regardless, and some of the singers at the premiere sang the original lines, claiming they had forgotten which words were censored.)