Romulan Guard
- Overarching Romulan military structure (TNG: "Unification II")
- Divided into legions
- First Legion
- More commonly known as the Romulan Star Navy (TLE novel: Serpents Among the Ruins)
- Fifth Legion (ENT Novel: Kobayashi Maru)
- Military research and development (ENT Novel: Kobayashi Maru)
- First Legion
- Ranks
- Officers
- Officer training at Imperial War College (TNG: "Face of the Enemy")
- Ranking, highest to lowest:
- Admiral
- Commander (equivalent to Captain)
- Subcommander (equivalent to Commander)
- Centurion (equivalent to Lieutenant Commander)
- Lieutenant (equivalent to Lieutenant)
- Sublieutenant (equivalent to Ensign)
- Officers are usually expected to serve until retirement or death, but resignations are allowed
- Enlisted
- Highest to lowest:
- Decurion (equivalent-ish to Petty Officer)
- Uhlan (equivalent to Crewman)
- Highest to lowest:
- Officers