The Masters of Arms were private or semi-private armies, organized on the same principles as other Masters organizations. They often acted as mercenaries. They were mainly active in the period before the establishment of the Stofonian state in 908.
For the Masters, war was self-supporting business, either through plunder or through payment by the states that hired them. A man usually joined his guild with nothing but a will to fight. The guild provided him with weapons, training, and shelter. In exchange, he was expected to show absolute loyalty to his guild. Recruits were drawn from all social classes.
This was in stark contrast to the more official form among the Stofonians at the time, in which men were generally expected to provide their own weapons, thus making war much more of a rich man's pastime.
The Masters were thus able to gather a larger number of men, and arm them better, than any contemporary government could do on its own. Their success was so famed that they were even hired by clients within the Elosian Empire, the superpower of the day.
In 908 the guild led by Ayst Inst took over the government of the city of Stofstans, and became the standing army and the foundation of the Stofonian state. From that time on, other private armies were no longer tolerated as competitors to the new state army. Some groups were absorbed and became divisions within the King's army, others lost members to the standing army by attrition, and others were violently wiped out by the state forces. As the state founded at Stofstans gradually conquered the entire Stofonian-speaking world, the original private armies passed into history.
However, the name survived. The Masters of Arms of the City of Stofstans was re-constituted as a fraternal organization for present and former officers of the army. The head of the guild was always the King or Emporer.
This group came to have great power and influence. All attractive government offices, whether or not they were in any way related to the military, were open only to members. Entire professions, such as law, were closed to non-members as well.
So attractive was the lure of membership, that the Stofonian Empire very rarely resorted to conscription to fight its many wars, as recruits were never lacking. Eventually, guild membership was extended to include anyone who voluntarily served in the army, regardless of rank. This boosted recruitment further.
The guild did not die with the Stofonian Empire; it exists today with members drawn from the armed forced of various Post-Stofonian States. Membership is restricted to countries that continue to follow the Imperial practice of favoring the Masters. Ironically, this does not include the modern Republic of Stofonia. Thus, at present, the "Masters of Arms of the City of Stofstans" have no connection with the soldiers who actually protect that city.
The Masters have been active in Stofonian Restorationism.