The Imperial Senate Sentinels constituted a specialized unit within the Imperial Senate Guard, serving the interests of the Imperial Senate. Emperor Palpatine charged these individuals with the critical task of shielding the Jedi Temple on Coruscant against potential scavengers, and they underwent rigorous training to effectively neutralize and eliminate Jedi threats. The Sith apprentice Galen Marek faced these sentinels in combat during the year 2 BBY.
Functioning as a specialized detachment of the Imperial Senate Guard, the Sentinels shared visual similarities with the Royal Guards. However, instead of the Royal Guards' distinctive red attire, the Sentinels wore gray and white armor and robes, and their helmets bore a resemblance to those worn by Senate Guards during the later stages of the Clone Wars. To enhance their effectiveness, they were equipped with formidable force pikes capable of deflecting a Jedi's lightsaber, a crucial asset in fulfilling their duties. Their voices had a robotic quality, leading to speculation that they were cyborgs. While not officially part of the Imperial Military, the Imperial Senate Sentinels occasionally collaborated with military forces when the importance of an objective warranted their involvement, such as guarding the remnants of the Jedi Temple.
Palpatine personally selected the Sentinels for the assignment of guarding the Jedi Temple on Coruscant. Stationed at the temple, they maintained vigilance over the ruins, safeguarding them from looters and those seeking to exploit the secrets of the Jedi Order. However, their primary mission was to lie in wait for any returning Jedi, whom they were instructed to engage and eliminate. In 2 BBY, Galen Marek, the Sith apprentice of Darth Vader, made several visits to the Jedi Temple as part of his training, during which he encountered and fought against numerous Imperial Senate Sentinels. Despite their efforts, many Sentinels were defeated in these encounters. During his second encounter with Marek, they attempted to inform him about his impending detention due to the Emperor's quarantine order at the Jedi Temple, but on his third and final visit, they launched a preemptive attack without warning.
The Imperial Senate Sentinels were initially introduced in the Playstation 3 and Nintendo Wii versions of the Star Wars: The Force Unleashed video game during the first visit to the Jedi Temple. In the game, they were simply referred to as "Imperial Sentinels," which should not be confused with the Imperial Sentinels who guarded Palpatine's Citadel on Byss. Their official designation and affiliation with the Imperial Senate Guard were established in the 2009 roleplaying-game supplement Galaxy at War.