Early service to ComStar
Marteen rose to the rank of Precentor Arcturus, serving on the Order's First Circuit during the reign of Raymond Karpov. As tensions increased between the extremely conservative Primus and a moderate leaning First Circuit, in an attempt at compromise Karpov named the more liberal Marteen as his successor, but this did not help matters. Disillusioned with a obstructionist First Circuit blocking his attempts to further fan the flames of the Second Succession War to bring about the Word of Blake, Karpov finally stepped down as Primus in 2875 with Marteen being sworn in as the new Primus.
Primus of ComStar
Initially, Marteen's liberal slant gave her a wider base of support than Karpov enjoyed during the final years of his reign, but while internally the Blessed Order was content, external issues would soon make her life difficult.
By start of her reign as Primus, many citizens on Terra had begun to chafe under the Blessed Order's rule of the world as benevolent dictators. While ComStar had begun to rebuild and restore Terra, many still remembered the glorious history of the Terran Hegemony and fomented for independence from the robe-wearing mystics of ComStar. Militant political groups staged protests at first, but soon stepped up their efforts to include terrorist-style bombings of ComStar re-education camps and other facilities.  
While less extreme than her predecessor, Marteen still recognized the threat represented by such groups and adopted a carrot and stick approach. On one hand she publicly made speeches supporting a "Terra First" policy and construction of twelve massive arcologies, creating jobs for millions and improving the standard of living for millions more while providing clear proof of the Order's support for the world. Secretly however, on the 3rd of March 2877 Marteen ordered Precentor ROM Joleen Weber to use whatever means necessary to suppress the Terran independence moment.   
In the summer of 2877, ROM agents exploded a bomb in the Euro-English Channel Tunnel which killed thousands of civilians instantly. Messages supposedly from members of Black December claimed responsibility for the bombing which they stated was meant to target the visiting pro-Marteen Precentor New Earth Jerrold Komandi, who narrowly avoided his date with destiny due to an unexpected and perfectly timed traffic jam.   
When ComStar sent huge number of rescue teams and relief equipment to save as many people as possible in the aftermath of what would be called the "Black December" Incident, in full view of the media of the Inner Sphere, Black December lost whatever support it might have once enjoyed. Turning the bombing into a propaganda bonanza, Marteen called for the members of the group to be caught and put on trial. ROM operatives allegedly discovered the hideout of Black December three months later, killing all its members in a shoot-out that erupted as they tried to arrest them.   
The news of the destruction of the group, coming on the heels of the start of construction of the first of the projected megacomplexes, was widely welcomed by the public with dissatisfaction with ComStar having all but evaporated.  Internally however several members of the First Circuit openly questioned the perfect timing and resolution of the event and accused the Primus of complicity in it. These rumors, along with the Order suffering an economic downturn in 2878 due to the massive funding required for the Terran arcologies, cost Marteen almost all support among the First Circuit.
Matters reached crisis point in 2882 when a conservative element on the First Circuit blocked Primus Marteen's proposal to raise transmission rates to all five Great Houses to help stablize the C-Bill exchange rate, as well as any future economic reform. Forced to kowtow to these conservatives to get her rate increase passed, three days after private meetings with the opposing members Primus Marteen announced Precentor Caph Dwight Kurstin from their number as her successor to the Primacy, the increase was then passed within the month.
Death and Legacy
The remainder of Marteen's reign was relatively quiet until her death in January 2901. While riding with Dwight Kurstin on a tour of the Caph's capital, her hover-limo swerved to avoid hitting some refugees and exploded after plowing into a building. All but Kurstin, who was able to escape moments before the explosion, died in the crash. The Primus's ROM security detail evacuated Marteen's successor to Terra and Kurstin was confirmed as Primus of ComStar shortly after.
The investigation into the crash raised a number of questions including the fact Andrea Marteen died from a sharp blow to the neck despite the fact the shock-cushioning material of her heavily-padded limo's interior was not compromised prior to the explosion. While inconclusive at best, the investigation reflected poorly on the new Primus and an enraged Kurstin fended off the accusations he murdered Marteen in a manner that only led more to question if he indeed had. 
The most notable contribution of Marteen's reign as Primus was the construction of massive Terran Arcologies and their positive effect upon ComStar's relationship with Terra, despite their cost literally and metaphorically to the Order and her support on the First Circuit. The nature of her death would also return the position of Primus to the dark trend where successor was rumored to have hastened the death of their predecessor.
Documents supposedly uncovered by Chandrasekhar Kurita during the Jihad allegedly claim Karpov's selection of Marteen satisfied both First Circuit politics as well as attempting to counter the more extreme goals of The Blood with which he now disagreed. Initially an peace loving outsider unaware of the Blood's existence, the ambitious Marteen was slowly introducted and agreed to support their more violent ways in return for their aid in in events such as the "Black December" Incident. 
Philosophical and/or political views
Selected by the ultra-conservative Karpov as a compromise with moderates on the First Circuit, despite her liberal leanings Marteen's reign saw her forced to engage in brutal actions that would not have been out of character for the crusty Karpov. Ironically much like Karpov, they would also cost Marteen her support on the First Circuit and force her to offer her selection for a successor to gain continued support from her opponents.
|Primus of ComStar
| Succeeded by|
- ComStar, p. 33 - "Slow Change"
- Jihad Hot Spots: Terra, pp. 154-155, "Terra under ComStar"
- ComStar, p. 34 - "Behind The Scenes"
- Intelligence Operations Handbook, pp. 104-105 - "Witch Hunts"
- ComStar, p. 34 - "Slow Change"
- ComStar, p. 35 - "Kurstin the Mad"
- The Blake Documents, p. 128 "The Not-Named"