The Monastic Order of the Black Friars of St Erecius stems from Lord Solar Macharius's own legion, Legio XXIII 'Nemesis'. Their teachings are modeled after the works of Macharius's bloodbrother, St Erecius, and places great weight on the individual's duties to Creation.
For centuries, the Order of the Black Friars have served the Kings of Pendrell as advisors and bodyguards, but after the Revan's Eve Plot in YE 996, they lost standing in the court due to their inability to prevent the assasination attempt on the king.
Six years later, in YE 1002, they were accused of blasphmy, and acts of enmity against Man. The case led to the Order being declared Anathema, and its lands being transferred in equal parts to the Royal House and the Ministerium. Ninetythree friars were imprisoned, seven were executed, and the Order was disbanded.
The fall of the Black Friars caused great harm to the Macharite philosophy, and in its stead, the Presbyterian teachings have gained hegemony of the Pendrellian society.