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 forebuilding
were built in the 1180s, and concentric walls with half-round
towers were added by Richard the Lion Hearted seventeen years later.