The Papacy of the main continent began with roving priests who moved between the natural barriers of Hain, spreading information, supplies, culture, and providing protection to those whom they visited. Though local villages would have their own warriors, as the few who moved about, the priests had better intelligence and always fell into a leadership role. Because it was dangerous to travel, priests always traveled with armed guards and were often trained in fighting themselves. As the priests became organized, they became an army. As the army grew, the general/head priest grew in power.
No one knows how the Pope first originated or when his identity became so closely guarded. Skeptics have been known to doubt his existence, but there does seem to be something within the walls of the Papal Fortress calling the shots, and if he doesn’t have the ears of God, he certainly has psychic powers enough to fake it.
The Church is law, and the church is order, and while it is not the entire culture, nothing occurs without its permission within the lands it controls. The Church consists only of men, nurturing boys into priests in hundreds of monasteries scattered throughout the country; from these pools the Cloister Army is formed, a highly-trained, fueled, and focused machine which tends to destroy whatever target it is able to reach.