12th Army (Star League)

12th Army (SLDF) 2765.jpg
12th Army
Unit Profile (as of 2765)
Parent Formation Star League Defense Force
Formed unknown

The Star League Defense Force's Twelfth Army was assigned to operations within the Lyran Commonwealth Military Region.[1]


The Headquarters of the 12th Army was located on Deia, from which the 12th Army was deployed throughout the border region between the Lyran Commonwealth and the Rim Worlds Republic. In addition to their assignment along the Rim Worlds border, the Twelfth was also assigned to monitor approximately half of the Commonwealth's border with the Draconis Combine.[2] As a result of this assignment, the 12th saw a lot of action during the Third Hidden War while engaged in "bandit hunting".[3]

The Twelfth Army's station along the Rim Worlds and Combine borders made it the most important Army in the Commonwealth Military Region. To insure they could protect the citizens of the Commonwealth the Twelfth worked and trained extensively with LCAF units. Though this working relationship allowed the two militaries to operate effectively on defense, the SLDF High Command worried that if the LCAF was ever an aggressor the Twelfth wouldn't be able to do their duty and stop the Lyrans. This potential problem hadn't reared up in 2765 however.[2]

The Twelfth saw a great deal of action during their bandit hunting activities. The Twelfth possessed an 80% success rate in responding to bandit raids. Only one bandit group in five escaped their divisions. This was only possible because the Twelfth could count on the LCAF to perform defensive duties, allowing the Twelfth's divisions to operate in an aggressive manner. Most of the bandits were down on their luck forces as expected, but several of these groups were equipped with better weapons and had more training. The Twelfth was attempting to gather more information about these bands, but any prisoners were immediately picked up by the Star League Intelligence Command.[2] (Later events would suggest that these bandits were sponsored by either the Rim Worlds Republic, Lyran Commonwealth, or Draconis Combine.)

When the Periphery Uprising demanded the deployment of additional SLDF forces into the Periphery, the 12th was one of the Armies selected to move as reinforcements, due to how quiet the border with the Rim Worlds Republic appeared to be. The 12th deployed into the Magistracy of Canopus and spent two years engaged in operations there; the 12th took relatively moderate damage during the Periphery campaign, losing six Divisions and an Independent Regiment to combat losses and a seventh Division to disbandment, but the bulk of these casualties were concentrated within XLII Corps. As a result, XLII Corps was subsequently merged with II Corps, reducing the 12th Army to a three-Corps formation.[3]


Rank Name Command
Commanding Officers of the 12th Army
General Eliud Felischhauer 2765[3]


Different per Unit.

Corps of the 12th Army[edit]

Composition History[edit]


  • 6 BattleMech Divisions[3]
  • 13 Infantry Divisions[3]
  • 9 Independent Regiments[3]


  1. The Star League, p. 145, "Twelfth Army"
  2. 2.0 2.1 2.2 Field Manual: SLDF, p. 147
  3. 3.0 3.1 3.2 3.3 3.4 3.5 Historical: Liberation of Terra Volume 1, p. 44, "Thirteenth Army"