Early service to ComStar
Kurstin rose to the rank of Precentor Caph, serving on the Order's First Circuit during the reign of Andrea Marteen. As tensions increased between the moderate Primus and the First Circuit over the economic downturn the Blessed Order suffered 2878 as a result of the massive funding required for Marteen's Terran arcologies, a conservative element on the First Circuit blocked Primus Marteen's proposal to raise transmission rates to all five Great Houses to help stabilise the C-Bill exchange rate. After they also threatened to block any future economic reform, Marteen was forced to kow-tow to this conservative power-bloc to get her rate increase passed. Three days after private meetings with the opposing members Primus Marteen announced Kurstin from their number as her successor to the Primacy. The rate increase then passed within the month.
Kurstin finally rose to the Primacy after Marteen suffered a fatal accident in January 2901. With Kurstin riding with Marteen on a tour of Caph's capital, the Primus's hoverlimo swerved to avoid hitting some refugees and exploded after ploughing into a building. All but Kurstin, who was able to escape moments before the explosion, died in the crash. The Marteen's ROM security detail evacuated Kurstin to Terra and he was confirmed as Primus of ComStar within a month.
Primus of ComStar
Kurstin's reign as Primus was clouded from day one after the investigation into the crash raised a number of questions including the fact Andrea Marteen died from a sharp blow to the neck, yet 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, a situation worsened when the enraged Kurstin publicly denied any involvement in the accident and ordered the two investigators arrested and later executed. 
The depth of his paranoia only increasing as the weeks went on, Kurstin ordered ROM to investigate several members of the First Circuit to see if in-fact they were behind Marteen's death in an attempt to frame him. Matters became worse when Kurstin attempted to make his first appointment to fill a vacancy on the First Circuit, selecting his first cousin Dana Kurstin for the post of Precentor Barnard. With Dana a mere Acolyte of ten months, while the Primus claimed he was promoting her strictly on the merits of her skills and abilities, several members of the First Circuit, led by Precentor Kari Marshall, directly implied that her appointment was purely based on her family ties to the Primus. For the first time ever, the First Circuit vetoed her appointment, the paranoid Kurstin viewing the failure of his candidate as another sign the First Circuit wished to challenge and undermine him. 
Kurstin's instability initially was known only inside the Blessed Order, but in the lead-up to the state funeral of Andrea Marteen word of these rumours and suspicions somehow reached the leaders of the Successor States, with First Prince Joseph Davion and Captain-General Elisabeth Marik, herself a former Adept in the Order, refusing to attend Marteen's funeral. Now seeing enemies everywhere both within and outside ComStar in the wake of this public snubbing, upon discovering two young adepts were behind leaking the rumour, Kurstin ordered them both executed without trial, further damaging his already shaky support in the Order.
The final breaking point was a particularly stormy session of the First Circuit where Kurstin directly accused a Precentor Kohler of plotting against him, answering Kohler's denials by branding him a heretic, dismissing the First Circuit and ordering ROM to take him custody. Three hours after the end of the session Kurstin sent a message to the extremely sceptical members of the First Circuit indicating that Kohler had died from natural causes while still in custody.
Having lost all faith in the clearly insane Kurstin, the remaining Precentors of the First Circuit met in secret in the empty halls of the Court of the Star League at the urging of Precentor Procyon Gregori Hartford to discuss their limited options. With ComStar law making no legal provision for the removal of the Primus from office on health grounds, and his direct control over ROM preventing them from physically deposing him, Hartford suggested their best option was to leave Terra, both to see how Kurstin would react and to try and stop the spread of information of his condition to protect the reputation of ComStar.
Despite the wide political differences between liberal members such as Hartford and conservatives such as Precentor Marshall, all agreed the proposal was the best course of action, the First Circuit leaving Terra on April 20th. Infuriated upon learning of their departure, on April 30th Kurstin sent the infamous "Witch-Hunt Transmission", branding the First Circuit heretics and decreeing that they be burned at the stake for their heresy. While he intended it to be sent to every HPG station in the Inner Sphere, the First Circuit intercepted the message and Hartford responded by ordering the First Circuit HPGs to operate without central coordination from the Terran HPG, effectively imposing a Communications Interdiction against Terra itself.  
Now driven over the edge, Kurstin used JumpShip couriers to send orders to ROM to assassinate the First Circuit and eliminate any members of the Order felt to be disloyal to him, a bloody purge reminiscent of Conrad Toyama's Purification that rounded up the innocent and guilty in equal measure. Under the protection of some 100 ROM bodyguards, the insane Kurstin then proceeded to transfer his seat of office from Hilton Head to the Court of the Star League. Adopting the First Lord's throne as his own, Kurstin had the ashes of Conrad Toyama exhumed and engaged in conversations with the deceased Primus. In response to seeing their leader so mentally incapacitated, a number of his bodyguards attempted to desert, only for Kurstin to have their bodies drawn and quartered as a lession to those who might break faith with him. 
Even in the face of such dire threats, ROM itself mirrored the fragmentation of the Blessed Order between loyalist, rebels and those seeking to lay low and avoid taking either side, making waging an intelligence war difficult. With ROM's internal efforts hamstrung and the First Circuit's relatively successful attempts to prevent news of the Civil War leaking to the general public, by the fall of 2901 Kurstin set in motion Operation Winged Crusader. Contracting the services of three mercenary units passing through Terra and unaware of the isolated Primus's insanity, Kurstin assigned the mercenaries vintage SLDF equipment from ComStar's secret stockpile to arm them in preparation to assault and retake the First Circuit's HPGs by force. 
When word of Winged Crusader leaked to the exiled First Circuit and the Order as a whole, Kurstin's blatant attempt to use military force in contradiction to the will of Blake cost him yet more supporters. Having long feared that matters might come to this, Gregori Hartford activated his ace in the hole, smuggling a message back to Terra to a ROM agent known only as Saber. 
Death and Legacy
On January 3rd 2902, Saber entered the Court of the Star League, disabling all security systems and the two guards stationed outside the throne room, before shooting Kurstin through the head with a laser at point-blank range. Saber left no trace save for a copy of "The Word of Blake" lying on the throne room's marble floor.  
With even Hartford's fellow First Circuit shocked by the move, and the now leaderless mercenary troops standing down with Kurstin's death, the exiled Precentors of the First Circuit called for an immediate end to hostilities and requested a summit on Terra. Exceedingly brief, the First Circuit dictated terms of surrender to those who sided with Kurstin and selected Gregori Hartford as the new Primus of ComStar. Among Hartford's first actions was to orchestrate the most intricate cover-up operation performed by ROM, suppressing any evidence the ComStar Civil War occurred and fabricating documentation that Kurstin had simply resigned office, with no reference to his mental state. 
Elements of the fanatical Word of Blake would in fact cite the cover story as the true version of events, that while Kurstin lost touch with reality there was no all-out civil war, claiming that the entire conflict was invented by the secular ComStar as a ham-fisted means showing that disagreements such as that between the Word and the secular ComStar had occurred previously in the Order's history.
Documents recorded on the secret journal of secular Precentor ROM Victoria Parrdeau secured by Chandrasekhar Kurita during the Jihad angrily claim Kurstin's Winged Crusader and enlistment of mercenaries via encrypted cipher clauses that were included in all contracts signed with Mercenary Review Board ruined any chance to utilise those secret clauses to protect or inspire more widespread conflict against the Great Houses.
Parrdeau's journal also made the claim that while the bulk of Kurstin's "conversations" with the late Toyama were lunacy, there were occasional grains of truth, and that these were part of the reason for later Primus Adrienne Sims' supposed visions. 
In the documents relating to the Not-Named supposedly uncovered by Chandrasekhar Kurita at the same time, the narrative of the Blood indicated that Kurstin knew nothing of their existence and whose psychological profile showed he would not react favourably to them, a proverbial "loose cannon" who threatened to destroy all they had planned. While unable to directly influence Kurstin, the document indicated Gregori Hartford was of the Blood and rallied resistance against him to save both the Five as well as ComStar in general, enlisting his gene-sister Julia Hartford aka Saber to finally remove him when he launched Winged Crusader. 
|Primus of ComStar
| Succeeded by|
- ComStar, p. 33 - "Slow Change"
- ComStar, p. 35 - "Kurstin the Mad"
- ComStar, p. 36 - "To Reign in Hell"
- ComStar, p. 36 - "Kurstin the Mad"
- ComStar, p. 37 - "Sword of Justice"
- ComStar, p. 37 - "Kurstin the Mad"
- The Blake Documents, p. 115 "Through the Looking Glass"
- The Blake Documents, p. 117 "Through the Looking Glass"
- The Blake Documents, p. 129 "The Not-Named"