From the early days of cinema, Bulwer Lytton’s confused and popular novel has been put on screen, and not only in Italy. Apart from aversion of a few metres made in 1900 by Walter Booth in Great Britain, there was the Ambrosio version of 1908, directed by Luigi Maggi: in France this aroused the enthusiasm of Victorin Jasset, who considered it one of the best works produced in cinema since its beginnings. In 1913 Ambrosio undertook a remake, entrusted to Eleuterio Rodolfi, while Pasquali, simultaneously put into production its own version, directed by Enrico Vidali, they were obliged by the judgement in a case brought by Ambrosio for unfair competition, to change the title to Ione o gli ultimi giorni di Pompei. A planned third version, by Film Artistica Gloria, to be directed by Mario Caserini, was never to see the light of day.
Vittorio Martinelli, Non solo Scipione. Il cinema di Carmine Gallone, edited by Pasquale Iaccio, Liguori editore, Naples, 2003

The four completed versions of Gli ultimi giorni di Pompei straddle key years in the evolution of film form in which fundamental stylistic developments occurred with great rapidity. It is undoubtedly true that this evolution in film style was one of the key reasons why the novel was remade so frequently: it was believed that each version would improve on the previous by virtue of the possibilities offered by new technological and stylistic developments. (…)
In 1913 the principal point of critical reference in reviews of Gli ultimi giorni di Pompei [by Eleuterio Rodolfi] and Jone o Gli ultimi giorni di Pompei [by Enrico Vidali] was the rival version: while both versions were highly praised, few critics explicitly discussed the formal characteristics of either version. More recently, Barry Salt has described Gli ultimi giorni di Pompei [by Eleuterio Rodolfi] as “much more primitive”, although he does not elaborate his reasons for making this comment. Based on the extant copies, Gli ultimi giorni di Pompei has a lower average shot lenght (ASL) than Jone, although both films have relatively low ASLs in comparison with the figures quoted by Salt for both European and American films in the years 1912-1917. In terms of how this ASL relates to scene dissection, it can be noted than Gli ultimi giorni di Pompei exhibits much less articulation between shots than Jone. It does articulate movement across contiguous spaces in a series of shots, as in Glaucus and Ione’s flight through the rainstorm, but this is also true of much earlier chase films. It also sets up a basic alternation of point-of-view shots in the arena scene, although the matching is not very accurate and the alternation is not repeated enough to create a true shot-reverse-shot structure.
Alexander Marlow-Mann, Gli ultimi giorni di Pompei, or the Evolution of the Italian Historical Epic (1908-1926), in “La valle dell’Eden”, n. 6, September-December 2000