Castles were defensive weapons. Aggressive attacks could issue forth from them, but their main task was to provide a safe haven to peasants in case of attack, for the protection of knights and nobles, to present an image of power or stability, and to keep valuables safe.

       This 19th century engraving depicts Reginald of Chatillon's crusader castle of Kerak (in modern-day Jordan). It was from this base that Reginald harrassed Saladin's caravans in the later-twelfth century and thus threatend the Sultan's overall control of his newly acquired Mulsim Empire. Reginald believed that Saladin posed a deadly threat to the Latin Kingdom of Jerusalem and ought to be challenged and weakened at every opportunity. He was right about the threat to the crusader kingdom in the East.

       As it turned out in 1187, Saladin was not weakened enough, or was too greatly outraged by Reginald's attacks: Saladin won the Battle of Hattin in July, 1187 -- winning also the city of Jerusalem and most of the area of the Crusader Kingdom. So, Reginald gets much blame for his aggressive policy toward the Sultan.

       By the next century, the Muslims had pushed the Latins completely off the mainland, but some impressive remnants remained, such as the stout foundations of this Hostpitallers' Castle in Acre.

       The skill at building castles in stone was quickly transferred from the Crusader Kingdom to Europe, such that within about a half century of the First Crusade, King Henry II built this enormous castle at Dover. Even during World War II, it was still used as a defensive structure -- and it withstood Hitler's attacks: This unexploded V-1 rocket buried itself just outside the castle.

       The Rhine River in the Holy Roman Empire was dotted with stout castles, as Obervessel. The autonomy these structures provided, especially in Germany, often led to competing power centers which made it difficult for some Emperors to consolidate and unify central authority.

       It is worth exploring the differences between Early Stone Castles, and Later Stone Castles.