French playwright and librettist He wrote some 350 dramas  most of which proved extremely successful  and he became the most popular opera librettist of his time His librettos include Gioacchino Rossini's Count Ory (1828)  Vincenzo Bellini's The Sleepwalker (1831)  Gaetano Donizetti's The Elixir of Love (1832)  Giacomo Meyerbeer's Les Huguenots (1836)  and Giuseppe Verdi's The Sicilian Vespers (1855)