Four Crusader States were established in the Levant following the First Crusade.

These states were the County of Edessa, the Principality of Antioch, the County of Tripoli, and the Kingdom of Jerusalem.

They were organized along the feudal lines of Western Europe, with a small Catholic ruling class known as 'Franks.'

The Franks ruled over a much larger local population of Muslims, Eastern Christians, and Jews.

The states were in a constant state of warfare and faced persistent military pressure from surrounding Muslim powers.

Defense relied heavily on a network of massive, strategically placed castles, such as Krak des Chevaliers.

The military orders, the Knights Templar and the Knights Hospitaller, were crucial for the defense of the Crusader States.

The states' economies were based on agriculture and control of the lucrative coastal trade ports like Acre and Tyre.

Over time, a degree of cultural exchange and coexistence developed between the Franks and the local populations.

The Crusader States were gradually reconquered, with the final stronghold, Acre, falling in 1291.