Astra Militarum - Chain of Command: The tenets of centralised Imperial strategy are set by the High Lords of Terra themselves. The Lord Commander Militant passes on the dictates of this august gathering to Segmentum Command, who in turn hold responsibility for operations within their own designated regions of the Imperium. In practice, the distance and scale involved in the Imperium's wars render such centralised command elements little more than out of touch figureheads. Tales abound of Astropathic messages being received wildly out of sync with the events to which they pertain. During the infamous War of Foretelling, the Vonost System faced a questing tendril of Hive Fleet Leviathan. Despite initial successes, Imperial efforts were crippled after temporal distortion caused all of Segmentum Command's orders for the entire war to arrive in a single, garbled message. Compelled at gunpoint by the hidebound Commissar Teitzin to follow their orders to the letter, Segmentum Command's strategy fell apart in horrific fashion and Vonost was lost in less than a solar month. Were frontline officers to await and obey the word of their remote superiors in all matters, Mankind would be swiftly overrun.Instead, the practicalities of command fall to the officer of highest rank in any given Imperial theatre of war. Though assigned the Munitorum rank of General, native honorifics such as Lord Marshal or High Chenzin are often maintained. These officers are supported by a cadre of loyal personnel who between them comprise localised high command. Individual generals vary enormously in their approach, some coordinating their forces from well behind the lines -- possibly even from low orbit -- while others take to the field amid dedicated retinues of bodyguards. Surrounded by the chatter of Servo-skulls, the whispering scratch of auto-quills, and the barking voices of subordinates, wreathed in the reek of Promethium-smoke and holy censers, these men direct their mighty armies to victory in the Emperor's nameThere are very rare circumstances in which a higher level of command is necessary. In these times, the rank of Warmaster is bestowed upon a mighty and brilliant leader. This rank can only be conferred with the express consent of the High Lords of Terra, and such an individual is said to wield authority second only to the Emperor Himself. Several centuries can pass without a Warmaster being appointed and, because of the unrivalled power of the position, there is never more than one in existence at any one time. Due to the stigma associated with the title thanks to the deeds of the Arch-traitor Horus, it is not uncommon for other titles to be used in place of Warmaster, such as "Lord Solar." Such men lead star-spanning Imperial Crusades, or else the defence of entire Imperial Segmentae.Even the humblest Imperial Guardsmen outrank their counterparts who serve in the fighting forces of their homeworld, the Planetary Defence Forces or PDF; indeed, many veterans look down on those regiments whose only duty is to defend their own planet. These forces are perceived by some Guardsmen as having little combat experience. This is, of course, far from the truth, for the Imperium of Man is beset on all fronts. The relentless raids of pirates and encroachments by aliens are continually opposed by every planet's own military forces. Standing firm in the face of brutal horrors, these brave PDF soldiers fight and die just as well as their comrades in the Imperial Guard, but without the glories and honours won on distant worlds.