The USS Imperial (NCC-19018) was an Defiant-class exploration cruiser in service as Deep Space Five during the 24th century, under the auspices of Commander of Oralian sector Operations. (Star Trek: Pioneer)

In 2381, Captain Benjamin Kelsoe was given temporary command of the Imperial, while the USS Pioneer was undergoing repairs, so that he and his crew could assist in the rescue of the USS Regal. During the rescue attempt, Kelsoe was abducted by Tyson Calok and his Coalition allies. After which the Imperial was disabled by the Coalition forces and left drifting in the Trajan Nebula. When the USS Independence arrived to assist, Captain Barbara Hessman received orders from Starfleet Command to set both the Imperial and Regal on self-destruct due to the extreme damaged aboard both ships and the immediate need to leave the area, and the lack of available ships and time to salvage the vessels. ("The Hornet's Nest")