HaloReach - CAPT Jacob Keyes

Captain Jacob Keyes, Commanding Officer of the UNSC Pillar of Autumn

The Commanding Officer is a billet position filled by officers that are in command of a particular duty, such as commanding a UNSC or leading a Marine unit. The status of commanding officer is duly applied to all commissioned officers who hold lawful command over a military unit, ship, or installation. Before a Naval officer is given control of a starship, they usually are given the rank of Captain.

In the Navy, commanding officer is the official title of the commander of a ship, but they are usually referred to as "the Captain" regardless of their actual rank, or informally referred to as "Skipper."[1] However, there have been Navy COs that held the rank of Commander, such as Captain Keyes before his promotion to Captain during the Battle of Sigma Octanus IV.[2] Marine Commanding Officers are issued orders by a higher ranking Naval Commanding Officer if on board a starship.[3] Marine Battalion COs (known as Battalion Commanders) are usually Lieutenant Colonels, though Majors can fill this position if a Lieutenant Colonel is unavailable. Marine Platoon Commanders are usually First Lieutenants, and Company Commanders are usually Captains.

Commanding officers may be of any commissioned rank. Usually there are more officers than command positions available, and time spent in command is generally a key aspect of promotion, so the role of commanding officer is highly valued, and in theory only goes to the best officers. In a unit, the commanding officer is often assisted by an Executive Officer (XO) or Second-in-Command (2i/c), who handles personnel and day-to-day matters. Larger units may also have staff officers of various responsibilities. Commanding officers are one of many billet positions that are allowed into Officer's Quarters.

In the UNSC Army, the commanding officer of a platoon is referred to as a Platoon Leader. The commanding officer of a company is referred to as a Company Commander, the commanding officer of a battalion is referred to as a Battalion Commander, and the commanding officer of a brigade is referred to as a Brigade Commander. At the division level and higher, however, the commanding officer is referred to as the Commanding General, as these officers are normally general-grade officers.

Known Naval Commanding OfficersEdit

NOTE: The list is incomplete.

Fleet Admiral


Vice Admiral

Rear Admiral



Lieutenant Commander


Lieutenant Junior Grade

Known Marine/Army Commanding OfficersEdit

NOTE: This list is incomplete.


  1. Halo:Combat Evolved Captain Keyes (O.S.): "Bridge to Cryo 2, this is Captain Keyes. Send John-117 to the bridge immediately." / Tech Chief Thom Shephard: "Captain, we'll have to skip the weapons diagnostics and I-" / Captain Keyes (O.S.): "On the double, crewman." / Tech Chief Thom: "Aye aye sir. {Pause} The Skipper seems jumpy, we'd better get moving. We'll find your weapons later."
  2. Halo: The Fall of Reach, page 161
  3. 3.0 3.1 3.2 3.3 Halo: Combat Evolved
  4. 4.0 4.1 4.2 Halo 2
  5. 5.0 5.1 Halo 3
  6. 6.00 6.01 6.02 6.03 6.04 6.05 6.06 6.07 6.08 6.09 6.10 6.11 6.12 6.13 6.14 Halo: Ghosts of Onyx
  7. 7.0 7.1 7.2 Halo: Evolutions - Essential Tales of the Halo Universe, The Impossible Life and the Possible Death of Preston J. Cole
  8. 8.00 8.01 8.02 8.03 8.04 8.05 8.06 8.07 8.08 8.09 8.10 8.11 8.12 8.13 8.14 Halo: The Fall of Reach
  9. Halo: Blood Line, Issue 1
  10. 10.0 10.1 Halo: First Strike
  11. 11.0 11.1 11.2 11.3 11.4 11.5 11.6 Halo: The Cole Protocol
  12. I love bees
  13. 13.0 13.1 Halo Wars
  14. Halo: Glasslands
  15. 15.0 15.1 Halo 3: ODST
  16. 16.0 16.1 16.2 16.3 Halo: Reach
  17. Halo: The Cole Protocol, page 354
  18. Halo: Evolutions - Essential Tales of the Halo Universe, The Mona Lisa
  19. 19.0 19.1 19.2 19.3 Halo: Contact Harvest
  20. Halo: First Strike, page 103
  21. Halo 3: ODST, Uplift Reserve
  22. 22.0 22.1 Halo: The Flood
  23. Halo: Reach, Exodus