The Imperial motif serves as a subtle musical element within Star Wars: Episode IV A New Hope, symbolizing the presence of the Galactic Empire. It should not be confused with the more recognized "Imperial March", which debuted in Star Wars: Episode V The Empire Strikes Back. Frequently contrasted with the Rebel Fanfare in both A New Hope and Star Wars Rebels: Spark of Rebellion, this musical cue was composed by John Williams and performed by the London Symphony Orchestra back in 1977.
Its initial appearance occurs early in A New Hope as Imperial forces board the Tantive IV, within the musical piece titled "Imperial Attack". The core of the theme consists of ominous low-pitched triplets, typically played by instruments such as timpani, cellos, basses, and trombones. It often acts as a counter-melody to the Rebel Fanfare during both "Imperial Attack" and "The Death Star". This motif has similarities to a recurring theme from Gustav Holst's composition "Mars, the Bringer of War." The motif features prominently aboard the Death Star, where it accompanies stormtroopers.
Some consider the Imperial motif to be an early musical representation of Darth Vader, although another brief motif is also present in A New Hope specifically for Vader. This secondary motif involves a subtle triplet melody played on bassoon, accompanied by minor key arpeggios on cellos. This theme is heard in "Imperial Attack" before Princess Leia's initial encounter with Vader and during R2-D2's escape pod launch. It reappears during the scene in Obi-Wan Kenobi's dwelling on Tatooine, played quietly on solo clarinet as Obi-Wan recounts Darth Vader's history to Luke Skywalker ("Tales Of A Jedi Knight"). It also accompanies scenes depicting stormtroopers in Mos Eisley ("Imperial Cruiser Pursuit") and on the Death Star ("The Stormtroopers", "The Trash Compactor", "Chasm Crossfire"). Both the Imperial motif and the Darth Vader motif were ultimately overshadowed by the "Imperial March" in the subsequent film, The Empire Strikes Back.
A revised rendition of the motif appears in the track "It's a Trap!" from Star Wars Rebels: Spark of Rebellion, when the Spectres rebel group infiltrates an Imperial Star Destroyer with the Ghost to liberate Ezra Bridger. It is also featured in "Gathering Forces" as part of the "Imperial Inquisition" track.
The Imperial motif makes a brief appearance in Rogue One: A Star Wars Story, during a scene showing Vader in a bacta tank within his castle on Mustafar ("Krennik's Aspirations") and in a scene that takes place chronologically just before the aforementioned boarding of the Tantive IV, acting as a musical foreshadowing of A New Hope ("Hope"). The theme can be heard briefly in Solo: A Star Wars Story during the train heist sequence, coinciding with the arrival of the range troopers.
The Imperial motif is deployed to signify the new stormtroopers in the Star Wars: The Bad Batch episode "War-Mantle."