Army and stromtrooper core(which was different from the army) would be something like this.(this is highly based on most earth army's, such as UK, the USA, Australia, France, Sweden and some others, some i have used more then others) NCO Private Lance Corporal Corporal Sergeant Officers Second Lieutenant Lieutenant Captain Lieutenant Major Major Lieutenant Colonel Colonel High Colonel Brigadier General Major General Lieutenant General General High General Grand General The Navy would be something like this (this is being highly based on the RAN because the the only earth navy i know of by heart) NCO seaman Petty Officer Chief Petty Officer Warrant Officer officer Midshipman Sub Lieutenant Lieutenant Lieutenant Commander Commander Captain Line Captain Rear Admiral Vice Admiral Admiral High Admiral Grand Admiral and starfighter command would be something like this(this is also heavily based on the RAAF and RAF, because their the only air forces i know, I'm also not going to do the NCO's in this.) Pilot Officer Flying Officer Flight Lieutenant Squadron Leader Wing Commander Group Captain Flight Commodore There are more ranks then this for starfighter command I'm just nor sure what they would be all of the above has been guess work by mixing real life military force to try and get the Imperial rank system, I'm going to be mostly wrong, if nothing else then because Ive based it on the commonwealth countries more then any other and the imperial system is most likely based on the USA Edit: added more star wars related ranks(all the ranks starting with High) changed the wording of some ranks as well