The Aragonese civilization is based on Medieval Catalonia, a small region in eastern Spain. They were able to hold their own on land and were part of the Reconquista. They also had a Mediterranean empire that reached Athens in the late 13th century. In contrast to other Iberian civilizations, the Aragonese are most powerful in the mid-game with a strong economy that carries them through the Castle age.
As an infantry civilization with Mediterranean architecture, the Aragonese have several bonuses like receiving 100 of every resource (except stone) when constructing a town center in the Castle age, starting with +25 of every resource, land military units attacking 5% faster, and faster building of barracks, stables, archery ranges, and siege workshops. The team bonus is that fish contain 50% more food.
Their castle unique unit is the Andalid, which is a fast-attacking infantry that deals trample damage to all adjacent units. It is strong against trash units and infantry but weak against archers. They also have a second unique unit, the Almogavars, which is a fast light raiding infantry unit that is great at raiding and strong against cavalry.
Their tech tree grades are good overall, with a strong infantry presence and a decent cavalry and navy. They lack certain upgrades in the blacksmith, siege workshop, and defenses, but have a strong economy.
The Aragonese excel in the early and mid-game with their formidable Castle age, but weaken in the late game without certain upgrades and good trash units. Their diverse set of infantry units still make them a strong late-game option.