Note: X and Y are coordinates (light years on XY plane) relative to Terra at (0, 0)
Marcus neighbouring systems
|X:Y Coordinates||-58.94 : -15.558[e]|
| Jump point
|Moons||4 (Bandi, Cele, Palila & Washi)|
|Atmospheric pressure||High (Breathable)|
|Highest native life||Mammals|
|Ruler|| Evagelos Gillis (Governor)|
Diego Corridan III (Planetary Legate)
- 2271 - Inhabited world 
- 2366 - Terran Hegemony 
- 2571 - Terran Hegemony 
- 2596 - Terran Hegemony 
- 2750 - Terran Hegemony 
- 2765 - Terran Hegemony 
- 2767 - Amaris Empire 
- 2771 - Amaris Empire 
- 2772 - Terran Hegemony (from September)
- 2784 - Terran Hegemony 
- 2785 - Free Worlds League 
- 2786 - Free Worlds League 
- 2822 - Free Worlds League 
- 2864 - Free Worlds League 
- 3025 - Free Worlds League 
- 3030 - Lyran Commonwealth 
- 3040 - Federated Commonwealth 
- 3052 - Federated Commonwealth 
- 3057 - Free Worlds League 
- 3062 - Free Worlds League 
- 3067 - Free Worlds League 
- 3077 - Word of Blake Protectorate 
- 3130 - Republic of the Sphere 
Marcus is a hostile world with an oppressive atmosphere. Settled in the early years of the Terran Hegemony to exploit the abundant radioactive materials, Marcus eventually hosted Orguss Industries. During the Amaris Civil War the Rim Worlds troops garrisoning the world forced the population to work triple shifts at the BattleMech plant and in the uranium mines. After five years of occupation nearly three million people of the planet's population was killed in mines and factories.
The fall of the Star League found the Free Worlds League in possession of Marcus. Though the industrial complexes were valuable to the Free Worlds, they also made Marcus a tempting target for raids from the Commonwealth. After centuries of raids and damage, the planet's economy was in decline and Marcus' future looked bleak. This led to a short lived cult that encouraged suicide as a way of reaching "Culmination". The cult was short lived as its members eventually killed themselves.
Fourth Succession WarEdit
Following the sudden invasions of several League worlds by the Tikonov Free Republic and a daringly successful invasion of Callison by mercenaries employed by the Lyran Commonwealth in mid-3029, Captain-General Janos Marik found himself in the midst of an unanticipated crisis. In addition to the conquest of Callison, LCAF communications traffic and movements had spiked sharply, creating the impression of an impending offensive against the League. Faced with what he believed to be the plausible threat of a large-scale attack aimed at the region of the League near Terra, Janos was more concerned with saving the six or seven assorted BattleMech regiments present within the region than he was with retaining the worlds, as he believed that the offensive would most likely be aimed at snipping off the corner of the League closest to Terra - and to both the Federated Suns and the Tikonov Free Republic. Marcus was one of the systems abandoned by Janos, who would learn later that he had been deceived by an effective campaign of smoke and mirrors arranged by the Commonwealth General of the Armies, Edward Regis, to deter the League from launching an invasion of the Commonwealth while the LCAF was heavily committed to its invasion of the Draconis Combine.
Marcus was invaded in the Free Worlds League's first wave of Operation Guerrero by the Seventh Free Worlds Legionnaires, the Fifth Marik Militia, and the Twelfth Atrean Dragoons. The defending FedCom troops sacrificed a 'Mech regiment in order to escape.
The Word of Blake incorporated Marcus into the Protectorate during the Jihad, but Marcus was liberated by allied coalition forces in July 3077 as a part of Operation SCOUR. In June 3077 the First Kell Hounds Regiment led by Akira Brahe raided Marcus as part of Operation SCOUR and engaged the Marcus Protectorate Militia in several cities. The unit was also able to take and destroy a WoB arsenal hidden under stored grain in three of the buildings of a hidden firebase. Less than a month later, a Coalition assault force formed by the Third Lyran Guards, the Clan Wolf-in-Exile Beta Galaxy and the Marlette Crucis March Militia landed as part of the real invasion they shattered the rest of the militia. During the assault by the Coalition troops, several million tons of foodstuffs ready for shipment were destroyed. This led to extreme economic effects as the shipment was critical to their economy.
The Word of Blake responded by dispatching a combination of hired mercenary (in the form of the Canned Heat, Clifton's Rangers, The Furies and the Stealthy Tigers to retake Marcus on the 11th of August; the coalition forces including the 20th Marik Militia had no choice but to retreat to the nearby world of Dieudonne. Two teams of ComStar affiliated Blake's Wrath units destroyed the uranium mines to deny them to the Word of Blake. The mercenaries the Blakists had sent were not concerned with limiting collateral damage, and when word of the Coalition's conquest of Terra reached them, the natives (aided by ComStar) overthrew their mercenary overseers, though some of them had already escaped when the fall of Terra news had arrived.
- Iron Guard
- Wylie's Coyotes
- Twelfth FedCom RCT
- Twelfth Atrean Dragoons
- Dark Age: Republic Worlds (3130), p. 186, "Marcus World Profile"
- Handbook: House Marik, p. 16, "Free Worlds League Founding "
- Handbook: House Liao, p. 17, "Capellan Confederation Foundation ]"
- Handbook: House Liao, p. 25, "Capellan Confederation After Age of War ]"
- Historical: Reunification War, p. 159, "Inner Sphere - 2596"
- Era Report: 2750, p. 37, "Inner Sphere - 2750"
- Historical: Liberation of Terra Volume 1, p. 11, "Inner Sphere - 2765"
- Historical: Liberation of Terra Volume 1, p. 104, "Rim Worlds Republic -  Map"
- Historical: Liberation of Terra Volume 1, p. 138, "Operation LIBERATION Wave 1 [July 2772 - December 2774]"
- Historical: Liberation of Terra Volume 2, p. 118, "Digesting The Hegemony"
- First Succession War (Source Book), p. 25, "Inner Sphere -  Map"
- Handbook: House Marik, p. 34, "Free Worlds League after First Succession War "
- First Succession War (Source Book), p. 113, "Inner Sphere -  Map"
- Handbook: House Marik, p. 38, "Free Worlds League after Second Succession War "
- Handbook: House Marik, p. 42, "Free Worlds League after Third Succession War "
- Historical: War of 3039, p. 133, "Inner Sphere - 3040"
- Field Manual: Updates, p. 159, "Free Worlds League Deployment Table"
- Jihad: Final Reckoning, p. 57, "The Jihad in Review"
- Map of the Inner Sphere 3130
- NAIS The Fourth Succession War Military Atlas Volume 2, p. 87, "Conclusion"
- Handbook: House Marik, p. 51, "Free Worlds League after Fourth Succession War "
- Shattered Sphere, p. 74, "Operation Guerrero, First Wave"
- Total Chaos, pp. 169-170 "HOUNDS OF WAR"
- Total Chaos, p. 164-165, "MARCUS"
- Total Chaos, p. 164
- Jihad Hot Spots: Terra, p. 59-60, "Chaos Eternal: Blood And Fury"
- Total Chaos, p. 165
- First Succession War (Source Book), p. 138, "First Succession War Deployment Table - FWLM"
- Historical: War of 3039, p. 141, "Deployment Table"
- 20 Year Update, p. 27, "Federated Commonwealth Deployment Table"
- Objective Raids, p. 19, "FedCom Deployment Table"
- Field Manual: Free Worlds League, p. 112, "Free Worlds League Deployment Table"
- Field Manual: 3145, p. 145, "Republic Armed Forces - Republic Remnant"
- 20 Year Update
- Dark Age: Republic Worlds (3130)
- Era Report: 2750
- Field Manual: 3145
- Field Manual: Free Worlds League
- Field Manual: Updates
- First Succession War
- Handbook: House Marik
- Historical: Liberation of Terra Volume 1
- Historical: Reunification War
- Historical: War of 3039
- Handbook: House Liao
- Jihad: Final Reckoning
- Jihad Hot Spots: Terra
- Map of the Inner Sphere 3130
- NAIS The Fourth Succession War Military Atlas Volume 2
- Objective Raids
- Total Chaos
- Shattered Sphere