Stone towers appeared early in the Loire River valley. The massive ruin at Langeais, recently dated 992, was once a broad tower with four corner turr… - Marilyn Stokstad

Castles continued to be the focus of economic activity as the center of an agricultural domain. Wealth continued to be measured in land and its produce. The only access the lord had to his wealth was to move from one estate to another consuming products from the harvests. Housing and feeding a household including retainers and servants required vasts amount of food and space for food preparation.

At the end of the Middle Ages, castles began to lose their military function, but not their psychological impact as a symbol of authority. Gun powder and cannons supported armies of mercenary troops, and the garrison forts built to house them adopted the crenellated walls of private aristocratic castles. By the sixteenth century, professional soldiers lived in barracks, a few officers and the governor had finer quarters, and kings and nobles merely directed the operations from distant palaces where battlements had become purely symbolic decoration. The Battle of Crecy between France and England in 1346 is traditionally considered to be the first use of cannons on the battlefield. At first the noise and smoke created by the explosion terrified horses and men, and wreaked more havoc than the projectiles. Early cannons could be more dangerous for the gunners than for the enemy, but military engineers rapidly developed the weapons’ power and accuracy. A castle’s high walls and towers made easy targets for gunners whose power and accuracy reduced once formidable medieval buildings to rubble. Mining became more successful because the attackers could put explosives under the walls.

By the time Henry II Plantagenet (r. 1154–89) was crowned king of England in 1154, baronial castles outnumbered royal castles. A tough, dynamic ruler, Henry began to rectify the situation at once. In the north, King Malcolm of Scotland surrendered to him, giving Henry significant castles in Scotland and in the border territory. Many older castles like Windsor were strengthened. At Dover the masonry great tower and fore building were built in the 1180s, and concentric walls with half-round towers were added by Richard the Lion Hearted seventeen years later.