Hired forces are predefined armies which may be temporarily controlled by hiring them with 
Gold. Hired forces cannot be used to Raid. There are two types of hired forces: Mercenaries and Holy Orders.
Mercenaries
Mercenaries are armies that can be hired by characters for 3 years. Each culture generates between one and three Mercenary Companies depending on the number of counties of that culture, with each additional company being bigger and more expensive than the previous one. They will pick a County of their Culture as their headquarters and will be available to be hired by anyone within Diplomatic Range of that County. Mercenary armies come with one or more specific Men-at-Arms Regiments and will also contain a number of Knights.
Rulers are allowed to go into Debt up to 2 years in order to hire Mercenaries.
Mercenary Regiments reinforce 3 times faster than regular ones.
Holy orders
Holy orders are military organizations that can be hired by characters who are at war with a Ruler whose Faith is considered Hostile or Evil. Only a single holy order can be hired at a time and as soon as the war ends holy orders are dismissed. All members of a holy order gain the 
Order Member trait.
Holy orders can own Holdings, which provides them with Taxes and 200 Levies. If a holy order loses all its Holdings it is disbanded.
Rulers who have Kingdom or Empire titles may vassalize holy orders of the same Faith, which allows the said Ruler to use the holy order for free or take its Holdings. They can also create a holy order via a decision. Each Ruler can only create one holy order. If a Ruler creates a holy order, they may get events that allow them to grant Holdings to the new holy order.
Courtiers can be asked to join a holy order if the faith's View on Gender doctrine allows. If the courtier accepts, the ruler will gain Piety while the courtier gains a Level of Devotion.
When a holy Order is created, its name is selected from a list of historical holy orders. When the list ends, randomly generated names will be used. The following is a list of historical names that will be used for the creation of in game holy orders.
Warriors of the Cross, Knights of the Chalice, Order of the Holy Communion, Knights of the First Gospel, Guardians of the Shroud, Knights of the Reliquary, Knights Templar, Knights Hospitaller, Teutonic Order, Order of Calatrava, Order of Alcantara, Knights of Santiago, Order of Saint Patrick, Brotherhood of the Holy Sepulchre, Knights of the First Patriarchate, Order of the Virgin Mary, Order of Saint Anthony, Order of Saint Addai, Warriors of the Hadith, Warriors of the Wahy, Companions of Hira, Hashshashin, Bektashi Order, Haruriyya, Herem Warriors, Immortals, Ahura Mazda’s Champions, Fire Walkers, Zurvan’s Chosen, Army of Light, Servants of the Patricians, Jomsvikings, Faithful of Tyr, Odin’s Valkyries, Chosen of Freyja, Lords of the Sky, Spirt Guardians, Possessed, Servants of the Pangool, Watchers, Warriors of Perun, Chosen of Perkunas, Sons of Kalevala, Chosen of Ashoka, Guardians of Bodh Gaya, Sangha of the Stuggle, Warriors of the Illuminated Heart, Shakyan Faithful, Followers of Arjun, Bulls of Rishabha, Jivas of Madhya Loka, Guardians of the Lotus Ocean, Sacrifices of Devloka, Taltos of the Field, Myrmidons, Priesthood of Ares, Guardians of the Five Khandro, Servants of Melek Taus, Warriors of Mother Sun, Warriors of Father Moon, Warriors of the Temple, Warriors of Mundhum.