Third Succession War

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The Third Succession War was an era of constant but low-intensity warfare between the Successor States. After the devastation of the First and Second Succession Wars, and the widespread loss of Star League-era technology, the Third Succession War was typified instead by innumerable cross-border raids mounted by small units over the ever-decreasing resources and technology that remained.

It began in 2866 and lasted for over a century and a half before petering out. Officially the year 3025 is given as the end date[1] but in reality low level conflict continued across the Inner Sphere right up until the Fourth Succession War erupted in 3028. (See End Date below.)

By the end of the conflict none of the Successor States had succeeded in destroying any of their opponents, although some (especially the Capellan Confederation) had suffered significant territorial losses to their neighbors. The overall technological standard of the Inner Sphere continued to decline during this era, a situation covertly abetted by ComStar which advanced its own agenda.

Start Date 2866
End Date 3025
Location Entire Inner Sphere
  • Minor territorial gains or losses
  • Technology continues to decline
  • No Successor State is destroyed



After three decades of high-intensity warfare, the Second Succession War spluttered to a conclusion as fighting tapered off in 2863. As with the similar conclusion of the First Succession War, with the conflict ending due to both military and economic exhaustion of all parties rather than any decisive victory, tensions between the Successor States remained high. Despite this, many hoped peace would prevail as the Inner Sphere went nearly two years without conflict, with the Lyran Commonwealth's Estates General and Free Worlds League Parliament both pressing for stand-down of their respective militaries, a refocusing on civilian reconstruction and end to wartime austerity measures.[2][3]

In response to efforts by these parties, Archon Elizabeth Steiner attempted to broker a formal peace treaty with Captain-General Philippa Marik in 2864, the success of these prompting the Captain-General to request these efforts be expanded to include the other Successor States. Representatives from all five houses met on New Earth in November 2864, but it soon became clear just how divided the Inner Sphere remained. The Draconis Combine representative indicated he was nothing more than an observer and that any treaty the others agreed on would be approved or rejected by Luthien at a future date; he was arrested and executed by the Lyrans as a spy. The Capellan Confederation refused to sign any treaty that did not make provision for the return of all the territories it had lost in last two wars — which the Free Worlds League and Federated Suns vociferously opposed, with the Federated Suns representative Luther Davion making equally unrealistic claims for the other Houses to accept House Davion for position of First Lord. The talks collapsed after seven fruitless weeks with nothing being achieved.[3][4]

'Mech in battle during the Third Succession War.

A group of Capellan and Free Worlds businessmen under the banner of the "Peace of Money Movement" likewise attempted push for a permanent peace treaty, but aside from First Prince Michael Davion, none of the other Successor Lords would give them the time of day, with a number of the other Houses convinced that First Prince Michael's enthusiastic and lavish support meant the movement was actually a Davion plot and the movement's claims of the Lyrans profiteering from the previous conflict alienating the Commonwealth.[5][6]

While many in the Inner Sphere hoped peace had finally come even if the formal attempts at peace treaties had failed, the bitter animosities between the Successor States meant conflict could just as easily resume, needing only to be triggered by those who wanted the war resumed, such as the quasi-religious communications company ComStar. Focused on the supposed "Word of Blake", ComStar guarded and preserved the Star League's technological secrets in the belief that when the Inner Sphere collapsed after the Great Houses had destroyed themselves, ComStar would rise to power as the savior of humanity. Seeing the prophecy foretold by the Blessed Blake endangered when Precentor ROM provided evidence that Inner Sphere would likely recover the bulk of Star League LosTech within three decades, in 2866 Primus Raymond Karpov and the First Circuit authorized ROM to filter information about the so-called Shadow War in the Draconis Combine between elements of the Internal Security Force loyal to Coordinator Miyogi Kurita and his sister Roweena to agents of Lyran Commonwealth and Federated Suns. Just as Karpov had hoped, in typical Kurita fashion when Miyogi learned that outsiders knew of the Combine's internal troubles and with Lyran traders making embarrassing inroads in the Rasalhague Military District, the simmering tensions along the Combine-Commonwealth border exploded into open warfare again on the Commonwealth's coreward border that soon swept across the entire Inner Sphere, signaling the beginning of the Third Succession War.[7][8][9]


The intensity of this conflict never approached that of either the First or Second Succession Wars. This lessening was more likely due to reduced military capacity rather than a change of tactics. The scavenger necessities that had begun to emerge during the Second Succession War carried over and each Great House rapidly realized that they needed to preserve their precious technical resources.[7][10][11]

Two main components of this era were the evolution of a set of informal rules of engagement, similar to old Terran chivalric values, and a neo-feudal system that solidified from roots that already existed. The rules of engagement were similar to the Ares Conventions whereby forces — usually composed of BattleMechs — fought over industrial facilities, but were restricted in their attacks on those facilities and civilians. Major battles, especially between mercenary units, were fought in stages with both sides allowing enemy Techs to enter the battlefield during periods of truce to attend to damaged 'Mechs. Especially important was a tradition of paying a ransom for safe passage after surrendering to a superior force. Also, JumpShips became strictly off limits as a military target as it was quickly recognized that without JumpShips, nothing would be possible and interstellar civilization itself would collapse.[7][10][11][12][13]

The feudal system evolved throughout the years because, just as during Terra's original Dark Ages, the capacity for central governance of the Inner Sphere's stellar nations had evaporated. As a result, each Successor Lord controlled their house via a hierarchy of nobles who, in exchange for full authority over their worlds, pledged their fealty and their 'Mechs to the service of their liege lord.[7][10][11]

Notable events of the Third Succession War[edit]

Operation FREEDOM[edit]

Operation ROLAND'S HORN[edit]

Operation KILLING STROKE[edit]

In 2949 newly invested Captain-General Thaddeus Marik started planning for a bold three-pronged invasion of the Lyran Commonwealth, with the main objective being the capture of Solaris and the former Terran Hegemony worlds of Denebola and Wyatt. Unfortunately upon presenting the plan to Parliament in 2950, the body firmly rejected the abrasive Thaddeus's demand for over 30 regiments of troops and extensive funding, underlining this by authorizing all worlds within two jumps of the Lyran and Capellan borders to invoke the Home Defense Act, which served to remove over two-thirds of the troops the Captain-General had requested.[14][15][16]

Refusing to be dissuaded from his grand venture, Thaddeus initiated low-level coups against minor states to install leaders more favorable to supporting him, as well as using his personal funds to hire ten mercenary units. Eventually launching a truncated version of his plan, Operation Killing Stroke would ultimately prove to be among the most costly and least successful offensives mounted by the Free Worlds League Military, netting only one world — Cavanaugh II — after three long and brutal years of campaigning.[14][15][16]

The Great Lee Turkey Shoot[edit]

Choosing to combat the increasing weakness of the Capellan ground forces in the late thirtieth century with overwhelming air support, after a House Marik raid near Ingersoll in 2952 was repulsed without a single Liao loss, Chancellor Ingrid Liao decided to launch a major offensive against the Federated Suns world of Lee, site of an AFFS regional supply center as well as a critical maintenance facility for aerospace fighters and increasingly rare Land-Air 'Mechs. Ingrid committed six fighter regiments (over 200 aerospace fighters) and a sizable ground force to the mission.[17][18][19][20][21][22]

The MIIO however learned of the plan well in advance, giving First Prince Peter Davion plenty of time to reinforce and direct the planet's defense himself. Thanks to their advance warning the Davion defenders met the Capellan forces in space, immediately assuming aerospace superiority. The Battle of Lee, later more commonly called the Great Lee Turkey Shoot, saw the sleeker and faster Davion aerospace fighters easily cripple over forty of the slower and older Capellan Thunderbirds and Eagles. The attacking 'Mechs, tanks and infantry consequently lacked sufficient air-cover and took heavy losses before being pushed off-world.[21][22][17][18][19][20]

The Deep Raid of 2987[edit]

Shortly after becoming Archon, Alessandro Steiner reviewed intelligence reports with his Strategies and Tactics division and came to the realization that a lull in the fighting between Houses Marik and Liao presented a unique opportunity. With both sides having pulled back to regroup and recoup their losses after years of heavy fighting, Alessandro correctly guessed the Marik troops on the border would be relaxed and vulnerable to an attack from an unexpected front, including those guarding a "secret" BattleMech factory under construction on the League world of Ling.[23][23][24][25][26]

Sending the elite Sixth Lyran Guards and the Fifty-fourth Fighter Support Wing aboard a JumpShip disguised as a commercial freighter, after two months of tense jumps, the Steiner forces reached the Ling system unchallenged and destroyed the BattleMech factory with only minimal losses to themselves. While the League forces exacted a measure of revenge by inflicting heavy losses when the Lyran forces made ill-considered strikes against Park Place, Ryerson, Irian, Nathan and Bordon as they made their way back to Commonwealth space, the loss of the vital BattleMech factory was a bitter blow.[23][24][25][26]

The Invasion of New Aragon[edit]

The Battle of Mallory's World[edit]

Draconis Combine forces invaded Mallory's World in 3013. Federated Suns First Prince Ian Davion was killed in a rearguard action, though the Kell Hounds mercenary unit managed to recover his body before it could fall into Kurita hands. Rulership of the Federated Suns thus passed over to Ian's brother Hanse Davion. The battle would continue into 3016 until the Kell Hounds, having earned the emnity of House Kurita, saw the withdrawal of the Kurita forces following the legendary Phantom 'Mech incident in that year.

The Battle of Halstead Station[edit]

In early 3014, Federated Suns First Prince Hanse Davion enacted a plan by his late brother Ian to raid Halstead Station. The initial idea had been to destroy a Draconis Combine supply depot close to the border, but the books from a rediscovered Star League era university were a much more valuable prize. Hanse Davion personally led three Federated Suns regiments of both 'Mechs and conventional forces into battle, but found that in addition to the known defenders, Coordinator Takashi Kurita and the elite Second Sword of Light regiment were present. The Davion forces achieved success but suffered heavy losses including the fiancé of Hanse Davion, "The Victor of Halstead Station". The books and data storage devices retrieved in the raid would be the basis on which the New Avalon Institute of Science was founded.

The Marik Civil War[edit]

In a particularly bitter chapter for House Marik, Captain-General Janos Marik saw his beloved brother Anton Marik rise up in rebellion in mid-3014. Colloquially known as "Anton's Revolt", it had been instigated by the clandestine machinations of Capellan Chancellor Maximilian Liao and also ComStar agitation. The rebellion lost momentum by early 3015 and culminated in a disastrous rebel attack on Calloway VI that gutted Anton's forces and served to estrange him from Wolf's Dragoons, his most important mercenary unit. The estangement soon led to a falling-out, and Duke Anton Marik ultimately died at the hands of the vengeful Dragoons, specifically the famous Black Widow Company in their inaugural deployment.

The Galtor Campaign[edit]

In 3025, Hanse Davion tried to lure Draconis Combine forces into attacking Galtor III to ambush and decimate them there, by pretending a Star League era lostech cache had been found on the planet. The plan went sideways when a real lostech treasure trove was discovered on Galtor III, and the Combine attacked with a much stronger force than anticipated. With both sides reinforcing their troops, the battle escalated into a multi-regiment battle the kind of which had not been seen in years if not decades. The Combine attack was narrowly repulsed.

Operation Doppelganger[edit]

Concurrently with the Galtor campaign, the Capellan Confederation attempted to and even briefly succeeded in replacing Hanse Davion with a doppelganger under Capellan control. Through the double House Liao worked to undo the fledgling alliance between House Davion and House Steiner, and also apparently weakened the Federated Suns leadership in the middle of the Galtor campaign. The plan was ultimately uncovered and foiled, however.

Conclusion of the Third Succession War[edit]

The Third Succession War drew to a close ironically not through any military victory but with another call for lasting peace. Recognizing humanity's slow but steady slide away from the glories of the Star League era and toward barbarism, Archon Katrina Steiner of the Lyran Commonwealth issued a Peace Proposal to the other House leaders in 3020. Hanse Davion, First Prince of the Federated Suns, was the only Successor Lord who welcomed the initiative. The result of their talks was the Federated Commonwealth Alliance Document, which Prince Hanse Davion and Archon Katrina Steiner signed on Terra in 3022. In addition to trade and military agreements, the F-C Document contained a secret provision betrothing the Archon's daughter in marriage to Hanse Davion. Though the marriage would not occur until the twelve-year-old Melissa came of age, this was the first step on the road to eventual unification of the Lyran Commonwealth and the Federated Suns.[11]

The other three Successor Lords were aghast at this sudden shift of power, which would lead to the eventual creation of a single state nearly as large as their three Houses combined. In October 3022, the Draconis Combine, the Free Worlds League, and the Capellan Confederation hastily signed the Concord of Kapteyn. Though not as far-reaching in scope as the F-C Document, it called for an end to active hostilities between the three states, who now pledge mutual defense against combined Federated Commonwealth as well as agreements to coordinate their overt and covert efforts to derail the Davion-Steiner alliance.[11]

Perhaps most active in the covert attempts was the Capellan Confederation under the leadership of Chancellor Maximilian Liao. Liao agents had already subverted Hanse Davion's brother-in-law Michael Hasek-Davion, who was now providing them with valuable military intelligence. When the Chancellor next initiated Operation DOPPELGANGER, a scheme to kidnap and kill Hanse Davion in order to replace him with a doppelgänger his scientists had created, he went too far. Davion eventually escaped capture and imprisonment and returned to his place on the throne, vowing revenge and setting the scene for the Fourth Succession War.[11]

End Date[edit]

While the Third Succession War officially ended in the year 3025,[1] it remains unclear why that is the case. No more specific date was ever given, nor is there any single event that could be considered an end point to the war. There is no indication either that anyone in 3025 would have considered that year to mark the end of the Third Succession War, suggesting the year was arbitrarily determined to be the end date only at some later point in time, presumably because the Fourth Succession War that began in 3028 was generally considered a new and dramatically different conflict as opposed to a continuation of the Third Succession War.

A theory is that 3025 was chosen because the annual Operation GALAHAD exercises, which heralded the Fourth Succession War, were held in 3026 for the first time. Another theory posits that the reason is the Concord of Kapteyn which was signed in 3022, ratified in 3024 and became effective on 1 January, 3025, thereby dividing the Inner Sphere into two power blocs - the FedCom Alliance and the Kapteyn powers.


  1. 1.0 1.1 BattleTech: 25 Years of Art & Fiction, p. 25
  2. House Steiner (The Lyran Commonwealth), pp. 66–67: "History - The Third Succession War - Lull - Once more into the Breach"
  3. 3.0 3.1 House Marik (The Free Worlds League), p. 38: "History - The Second Succession War - Last Chance for Peace"
  4. Handbook: House Marik, p. 37: "History of the Free Worlds League - Second Succession War"
  5. House Davion (The Federated Suns), p. 77: "History - Third Succession War - Man of Peace"
  6. House Kurita (The Draconis Combine), p. 74: "History - The Third Succession War"
  7. 7.0 7.1 7.2 7.3 ComStar, p. 32: "History of ComStar - War Renewed - The Karpov Legacy"
  8. House Kurita (The Draconis Combine), p. 76: "History - The Third Succession War - Is War the Natural State of Man?"
  9. Handbook: House Kurita, p. 54: "History of the Nation - The Third Succession War"
  10. 10.0 10.1 10.2 MechWarrior: The BattleTech Role Playing Game, p. 8: "A History of Human Space - The Succession Wars (2785-Present)"
  11. 11.0 11.1 11.2 11.3 11.4 11.5 MechWarrior: The BattleTech Role Playing Game, Second Edition, pp. 111–112: "Historical: Overview - The Succession Wars (2785-3030)"
  12. Handbook: House Liao, pp. 32–33: "History of the Nation - Third Succession War - Elastic Defense"
  13. Handbook: House Davion, p. 61: "History of the Federated Suns - Third Succession War - Rise of the Brotherhoods - Armistice - Back to Battle"
  14. 14.0 14.1 House Marik: The Free Worlds League, p. 42
  15. 15.0 15.1 Handbook: House Marik, p. 41
  16. 16.0 16.1 Field Manual: Free Worlds League, p. 8: "A House Divided - Politics of Command - Resolution 288"
  17. 17.0 17.1 House Liao (The Capellan Confederation), p. 50: "History - The Succession Wars - Shift to Aerospace"
  18. 18.0 18.1 House Davion (The Federated Suns), pp. 87–88: "History - Third Succession War - Knights of the Void"
  19. 19.0 19.1 Handbook: House Davion, p. 67: "History of the Federated Suns - Third Succession War - Rise of Brotherhoods - The Purge"
  20. 20.0 20.1 Handbook: House Liao, p. 34: "History of the Nation - Third Succession War - The Great Lee Turkey Shoot"
  21. 21.0 21.1 Technical Readout: 3025, p. 134: "SPR-H5 Sparrowhawk"
  22. 22.0 22.1 Technical Readout: 3025 Revised, p. 152: "SPR-H5 Sparrowhawk"
  23. 23.0 23.1 23.2 House Steiner (The Lyran Commonwealth), p. 77: "Alessandro Steiner"
  24. 24.0 24.1 House Marik (The Free Worlds League), pp. 46–47: "Concession to Parliament"
  25. 25.0 25.1 Handbook: House Steiner, p. 51: "Strategic Errors"
  26. 26.0 26.1 Technical Readout: 3025, p. 162