The Iron Crusade is the fighting forces of the Iron Kingdom in Final Fantasy XVI. These warriors consider it their holy duty to attack and pillage the other kingdoms of Valisthea, the devotion to the Crystalline Orthodox of the people of the Iron Kingdom making all states welcoming Dominants and Bearers pagan states.
The Crusade is divided into several battalions, whose commanders are nominally under the orders of the King, but in practice it is the priests of Crystalline Orthodoxy who lead the country, and they often accompany the warriors on their incursions into the continent.
Ironblood warriors are perceived by the other peoples of Valisthea as savages and barbarians, not least because they prefer to use clubs and two-handed axes rather than lighter weapons such as swords.
The Iron Kingdom also relies on a powerful navy to protect its territorial waters, where the Mothercrystal of Drake's Breath is located, and to send its men to attack other nations on the continent.