The saying "Long live the Empire" was commonly voiced by those who supported the Galactic Empire.
During both the Imperial Era and the New Republic Era, the phrase "Long live the Empire" served as a declaration of support within the Galactic Empire.
In 19 BBY, Barriss Offee, a former Jedi, joined the ranks of the Inquisitorius and encountered the Fourth Sister, Marrok, the Grand Inquisitor, and the Eleventh Brother. They all bowed as Darth Vader, a Sith Lord, arrived. The Grand Inquisitor, kneeling before Vader, proclaimed the enduring nature of the newly established Empire, and Barriss echoed the sentiment after putting on her new helmet. At some point between 9 BBY and 2 BBY, Admiral Thrawn uttered these words upon dispatching a segment of his fleet to Corvus (the planet), under the command of Morgan Elsbeth (the recently appointed magistrate), to initiate her mission. In 5 BBY, as Senator Mon Mothma delivered a speech against the Public Order Resentencing Directive, an individual within the Imperial Senate shouted "Long live the Empire." Following the Imperial Military's liberation of Chorin, a mining planet, from pirates, the inhabitants of Chorin City celebrated the Empire's longevity and the life of its ruler during a celebratory parade attended by Captain Tarl Sokoli.
During 9 ABY, Lady Bo-Katan Kryze's Mandalorian resistance attacked an Imperial Gozanti-class Assault Carrier located on the moon Trask. The captain of the Gozanti-class Assault Carrier contacted his superior, Moff Gideon, to request reinforcements. Gideon refused the captain's plea and concluded the transmission with "Long live the Empire." The captain echoed the phrase and then attempted to crash his starship to prevent the Mandalorians from capturing it. Gideon used the phrase once more during a gathering of the Shadow Council, where other members, including Captain Gilad Pellaeon and Commandant Brendol Hux, collectively repeated it. General Hera Syndulla of the New Republic Defense Fleet quoted the phrase in a sarcastic manner during her briefing with the Senate Defense Council following a clash with Imperial sympathisers at Facility 301G, pointing out that individuals who praised the Galactic Empire's continued existence were not the kind of individuals the New Republic wanted to recruit. Before initiating an extragalactic hyperspace jump during his escape from Peridea (the planet where Morgan met her end), Grand Admiral Thrawn reiterated the phrase aboard the Eye of Sion, concluding his praise of Ahsoka Tano.