The ship was part of Battle Group 3 at the Battle of 18 Scorpii in 2543. During the battle, the Thermopylae took moderate damage and would likely have been destroyed, but she and the rest of Battle Group 3 were saved by Insurrectionist forces.
- The ship is named for the famous Battle of Thermopylae, where the 300 Spartans made a last stand against the Persian Empire during 480 BCE
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