The Galactic Empire (known ingame as the Empire) is one of six playable factions in Sins of a Galactic Empire. It features ships with an emphasis on firepower, as well as technologies designed to intimidate and enhance the destructive power. Their fleets typically consist of powerful Star Destroyers and have a focus on quality over quantity.
Through research the Empire can gain access to the formidable Allegiance-class battlecruiser and the infamous Executor-class star dreadnaught (or Super Star Destroyer) as its Super Capitals. They also have access to several powerful mid- and late-game economic upgrades, including ship production bonuses.
Wookieepedia Article: Galactic Empire
The Galactic Empire, also known as the Empire, was the galactic government established by Supreme Chancellor Palpatine to replace the Galactic Republic in 19 BBY and bring Sith rule to the galaxy.
The Republic, which had lasted for at least 25,034 years, ended following a period of intense political turmoil and the subsequent devastation of the Clone Wars. After General Grievous was defeated at the battle of Utapau, and shortly before the leaders of the Confederacy of Independent Systems were killed on Mustafar by Darth Vader, Chancellor Palpatine (by then ruling with near-absolute power), began a purge of the Jedi Order, and then proclaimed himself Emperor of the galaxy and reorganized the Galactic Republic into "the first Galactic Empire" on the galactic capital.
Following the Declaration of a New Order, the Empire continued to consolidate its hold on the Galaxy through the utilization of fear and intimidation to keep star systems in line. During this time, rebellious factions arose to challenge the Emperor's rule, eventually giving rise to the Declaration of Rebellion and the creation of the Alliance to Restore the Republic, more commonly known as the Rebel Alliance. After five years of pan-galactic civil war and millions dead, the Alliance triumphed over the Empire in a climatic battle on and above the Forest Moon of Endor which resulted in the deaths of Emperor Palpatine, Darth Vader, several Imperial grand admirals, the destruction of the second Death Star, and the dispersal of a bulk of the Imperial Fleet to the Outer Rim and the Deep Core. Within months, the Imperial capital of Coruscant (then renamed Imperial Center) was captured by the Alliance and the New Republic declared.
Following the Battle of Endor, the Empire's power continued to wane and fracture as numerous flag officers and sector governors seceded from the Empire forming their own holdings. Over the following decades, the disperate warlord fiefdoms were unified and dispersed as one Imperial leader after another (including the once-then-twice dead Palpatine) vied to restore the then Imperial "remnant" back to galactic prominence. The Remnant allied itself with the New Republic and later Galactic Federation of Free Alliances in the struggle against the Yuuzhan Vong, and was pitted against the Confederation of the Five Worlds during the Second Galactic Civil War, resulting in defeat for itself and its would-be emperor, Darth Caedus (formerly Jacen Solo).
By 40 ABY, the Imperial Remnant was at peace with the Galactic Alliance and was again ascendant. This lead to an eventual restoration of the position of Emperor under the Fel dynasty, and the gradual onset of a cold war with the GFFA. In 137 ABY, the Sith-Imperial War ended with the capitulation of the Galactic Alliance, leading to the Galactic Empire being restored to rule. Not long after victory, newly crowned "Galactic" Emperor Roan Fel was deposed by One Sith leader Darth Krayt and the Second Imperial Civil War ensued.
With the defeat of Krayt and the One Sith-dominated Empire, the "Fel Empire" was restored as the legitimate Imperial authority under the rule of Empress Marasiah Fel, only daughter of former-emperor Roan Fel who was killed by his Imperial Knights after having fallen to the Dark Side of the Force. It was a founding member-state of the newly formed Galactic Federation Triumvirate alongside the Galactic Alliance and the Jedi Order, designed to share power between the major governments and ensure lasting peace in the Galaxy.