The Imperial Army is the largest branch of the Imperial armed forces, and has always been seen as the most important military arm. The Imperial Army is massive, so much so that outsiders cannot say for certain how large it really is. We do know, however, that the Army organizes it's divisions and armies into several different readiness categories. Category I units are active duty - theoretically combat ready. Category II units are reserve units and would require 30-90 days to be combat ready. And Category III units are inactive reserves that would require up to 6 months of preparation to be deployable.

Notable Imperial Army units include the following:

1st Combined Arms Army

2nd Combined Arms Army

5th Infantry Army

6th Combined Arms Army

Imperial Airborne Corps