Jérusalem is a grand opera in four acts by Giuseppe Verdi. The libretto was to be an adaptation and partial translation of the composer's original 1843 Italian opera, I Lombardi alla prima crociata. It was the one opera which he regarded as the most suitable for being translated into French and, taking Scribe's advice, Verdi agreed that a French libretto was to be prepared by Alphonse Royer and Gustave Vaëz, who had written the libretto for Donizetti's most successful French opera, La favorite. The opera received its premiere performance at the Salle Le Peletier in Paris on 26 November 1847.

The director of the Paris Opéra, Léon Pillet, had invited Verdi to compose an opera for the company in November 1845 and February 1846, but initially Verdi declined. This was the composer's first encounter with the Académie Royale de Musique, as the Paris Opéra was officially known. Amongst 19th century Italian composers, there had been an increasing interest in writing for Paris, where the combination of money, prestige, and flexibility of style were appealing. Musicologist Julian Budden provides examples of those composers who had crossed the Alps; amongst the most well-known were included Rossini and Donizetti as well as Vincenzo Bellini who, before he died in 1835, was planning a French grand opera.

However, Verdi had given some consideration of the idea of adapting one of the librettos written by Temistocle Solera in earlier years, librettos which music historian David Kimball regards as having something of grand opera in their structure.

After conducting the premiere of I masnadieri in London and within a week of Verdi's arrival in Paris on 27 July 1847, he received his first commission from the company, agreeing to adapt I Lombardi to a new French libretto. The adaptation meant that Verdi could "try his hand at grand opera" without having to write something entirely new, a strategy which both Donizetti and Rossini had employed for their Paris debuts.