Imperial Starfleet

"Terror must be maintained or the Empire is doomed."

- Spock, on Starfleet's mission

The Imperial Starfleet (Starfleet) was the naval forces of the Terran Empire in the Star Trek mirror universe.

Overview
The Imperial Starfleet was founded some time before 2154. Like the Empire itself, which was a dark, twisted version of the United Federation of Planets, the Imperial Starfleet was such a version of the Federation's Starfleet. Much of the personnel and equipment was nearly identical to the prime universe's Starfleet, although dark and twisted versions of their prime unvierse counterparts.

Under the direction of the Emperor, Starfleet conquered much of the Alpha Quadrant by the 23rd century, subjugating or destroying all those it came across. These included Klingons, Andorians, Vulcans, Denobulans, Halkans, and numerous other species. When Starfleet was not busy conquering new territory they were suppressing the rebellions which invariably occurred due to the despotic and oppressive natured of the Empire. Starfleet members would not hesitate to commit genocide when dealing with resistance.

Officers in the Imperial Fleet advanced in rank through assassination and employed their own personal henchmen amongst the enlisted ranks. Officers who advanced by assassinating their superiors included Sylvia Tilly, Hoshi Sato, Christopher Pike, James T. Kirk, and Mr. Spock. Officers who attempted assassination of superior officers included Pavel Chekov, and Wesley Crusher - both of whom failed in their attempts.

"I do not want to command the Enterprise. But if it should befall me, I suggest you remember my operatives would avenge my death. And some of them...are Vulcans."

- Spock, warning Sulu about the consequences of his assassination.

While successful assassination was rewarded with a subsequent rise in rank, it was still a dangerous prospect due to the reprisals that might result from the personal guard and other operatives of the deceased. It was considered especially dangerous if such persons were Vulcans.

Discipline on board Starfleet vessels was brutally harsh. Members were subjected to agonizers for the more minor offences, which was quite painful in itself. More serious offences would result in the member being placed in an agony booth, which tortured its victims. Such booths could slowly torture an individual to death if they were used for what was called the "full duration."

Primary Mirror Universe
After the 2267 crossover, Spock began a series of reforms to make the Empire a less aggressive and more benevolent organization. Due to his reforms the Empire was dissolved in favor of the Terran Republic in the late 23rd century. However the massive disarmament left Starfleet unable to repulse the Klingon-Cardassian Alliance, and Starfleet was defeated in the 2290s.

A successful rebellion in the mid 24th century led to the Terrans freeing themselves from decades of enslavement. Learning from their past mistakes they did not reconstitute either the Empire or the Imperial Starfleet, but instead created a new democratic Galactic Commonwealth and a fleet to support the new government.

Dark Mirror
After being framed by Kirk for treason, Spock was executed in 2279. As a result his reforms never got off the ground. Starfleet survived in to the 24th century, and fielded vessels such as the ISS Enterprise (ICC-1701-D).

Online
In the Star Trek Online permutation of the mirror universe, the Empire was resurrected after the successful Terran rebellion of the mid 24th century. By the early 25th century Starfleet had been reconstituted and helped the Empire once again become a major power in the Alpha Quadrant.