User:Rotaretilbo/Rank

Summary
As I have grown tired of argueing back and forth, I am putting together a page of all the ranks in the UNited Staes Navy and United States Marine Corps, then showing which of these ranks is confirmed in the Halo universe, and providing a source. There are still a few from Halo: The Fall of Reach without page numbers, but I'll have those page numbers shortly. There are also several I think are in the books, but can't look up because I don't have my copy of Halo: The Fall of Reach, and I wouldn't know where to look if I did. There are, of course, several that are not mentioned in the Halo series as far as I know.

Marine Corps

 * Private: Confirmed
 * Private First Class: Confirmed
 * Lance Corporal: Confirmed
 * Corporal: Confirmed
 * Sergeant: Confirmed
 * Staff Sergeant: Confirmed
 * Gunnery Sergeant: Confirmed
 * Master Sergeant: Confirmed
 * First Sergeant: Unconfirmed
 * Master Gunnery Sergeant: Confirmed
 * Sergeant Major: Confirmed
 * Warrant Officer: Unconfirmed
 * Chief Warrant Officer: Unconfirmed
 * Second Lieutenant: Confirmed
 * First Lieutenant: Confirmed
 * Captain: Unconfirmed
 * Major: Confirmed
 * Lieutenant Colonel: Unconfirmed
 * Colonel: Confirmed
 * Brigadier General: Unconfirmed
 * Major General: Confirmed
 * Lieutenant General: Unconfirmed
 * General: Confirmed

Navy

 * Crewman: Confirmed
 * Petty Officer Third Class: Confirmed
 * Petty Officer Second Class: Confirmed
 * Petty Officer First Class: Confirmed
 * Chief Petty Officer: Confirmed
 * Senior Chief Petty Officer: Confirmed
 * Master Chief Petty Officer: Confirmed
 * Warrant Officer: Confirmed
 * Chief Warrant Officer: Unconfirmed
 * Ensign: Confirmed
 * Lieutenant Junior Grade: Confirmed
 * Lieutenant: Confirmed
 * Lieutenant Commander: Confirmed
 * Commander: Confirmed
 * Captain: Confirmed
 * Rear Admiral Lower: Confirmed
 * Rear Admiral Upper: Unconfirmed
 * Vice Admiral: Confirmed
 * Admiral: Confirmed
 * Fleet Admiral: Confirmed

Conclusion
Of the 43 ranks that are possible in the Halo universe based upon the American Navy and Marine Corps, there are 9 unconfirmed. That means that 34 are mentioned. And there are also 0 ranks that contradict the American system, though there are a few titles that could be confused with ranks. Also, Eric Nylund confirms (here) that, when writing his books, he bases the UNSC ranking system off the American system. This, along with the fact that Bungie, Eric Nylund, and Microsoft are all Americans, heavily supports the theory that the UNSC ranking system is based upon the American Navy and Marine Corps ranking system.