The film series began with Star Wars, released on May 25, 1977. This was followed by two sequels: The Empire Strikes Back, released on May 21, 1980, and Return of the Jedi, released on May 25, 1983. The opening crawl of the sequels disclosed that they were numbered as "Episode V" and "Episode VI" respectively, though the films were generally advertised solely under their subtitles. Though the first film in the series was simply titled Star Wars, it later had the subtitle Episode IV: A New Hope added to distinguish it from its sequels and prequels.
In 1997, to correspond with the 20th anniversary of the release of Star Wars, Lucas released "Special Editions" of the three films to theaters. The re-releases featured alterations to the original films, primarily motivated by the improvement of CGI and other special effects technologies, which allowed visuals that were not possible to achieve at the time of the original filmmaking. Lucas continued to make changes to the original trilogy for subsequent releases, such as the first ever DVD release of the trilogy on September 21, 2004.
More than two decades after the release of the original Star Wars, the series continued with the long-awaited prequel trilogy; consisting of Episode I: The Phantom Menace, released on May 19, 1999, Episode II: Attack of the Clones, released on May 16, 2002, and Episode III: Revenge of the Sith, released on May 19, 2005.