Battle Castle: Dover 360 from Battle Castle on Vimeo.

The Story

Location: England


The build: Dover Castle was commissioned by King Henry II in the late 12th century as a mighty fortification to guard the region of Kent, situated at the shortest crossing between Britain and the Continent. Executed by the King’s finest engineer, Maurice, it cost more to build than any of Henry’s other projects. After the King’s death, his sons Richard, and then John, continued construction on the stronghold until it became the first concentric castle in Western Europe. Its magnificent square keep, intimidating forebuilding and innovatively-shaped towers live up to its reputation as the key to England.

The siege: This castle was besieged by Prince Louis of France in the early 13th century. Son of Philip II, Louis came to England to attempt to usurp King John during the First Barons’ War. He seized several fortifications and marched into London. Then he turned his sword on Dover. Prince Louis’ siege machines -like the perrier -faced several layers of defences, including a palisade, before he could even hope to storm the castle and attack its garrison, led by Hubert de Burgh. This vicious fight challenged Dover’s military power, and its outcome would determine the fate of the English crown.

Castle Facts


  • Dover Castle is one of the largest in Britain. The entire site occupies more than 141,000 square meters.
  • In total, work done on Dover Castle by Henry II, Richard and John cost some £8,250 – more than twice as much as was spent on the Tower of London during the same period.
  • The ground floor of Dover’s keep is believed to have been designed for storage. Interestingly, Maurice, the castle’s designer, put round-headed arches in its cross-wall. This almost certainly aided the store-keepers … but it lessened the defensive strength of the building.
  • When Dover was besieged by Prince Louis and his French forces in 1216, it had a relatively substantial garrison – accounts mention 140 knights, as well as a large number of men-at-arms.
  • Dover Castle was built by-in-large in the late 12th to early 13th centuries, but its location is believed to have been fortified for some 2,000 years. In fact, its unusual outline may have been designed to reuse a ditch and bank of an Iron Age hillfort and an earlier Saxon structure.
  • Henry II was a prolific castle builder. He spent money on no less than 90 English fortifications during his reign.
  • Dover’s keep was the last – and most expensive – of the great square keeps ever to be built. As such, it features most of the elements found in structures of this kind constructed in the 12th century.
  • Until Dover’s outer circuit of walls was finished under King John, the castle’s outer defences consisted largely of a moat and bank that were likely some 1,200 years old. When he came to the throne in 1999, the site was almost certainly still a giant construction zone.
  • During the siege of Dover, nobles from all around came to pay homage to Prince Louis, whose French army was attacking the castle. The most notable of these guests? Alexander II, King of Scotland.
  • In 1215, King John signed the Magna Carta – an ambitious document that, among other things, guaranteed all free men protection from illegal imprisonment and seizure of property. A committee of 25 barons was mandated to wage war if John failed to uphold it. He did … and they did.
  • Henry II acquired key territory on the Continent through his marriage to Eleanor of Aquitaine in 1152. She was previously married to King Louis VII of France, but he annulled the union after they failed to produce a son. The minute Henry married Eleanor, Louis lost control of more than half of his country.

Featured Structure: Towers

Created with Admarket’s flickrSLiDR.

Defensive towers come in several different forms. In castle building, the first of these structures appeared as part of the wooden palisades that fortified motte and bailey castles. Some towers are integrated into the walls. Others are structurally independent and flanked by stretches of curtain. Certain designs project out to make it easier for archers to cover adjacent stretches of wall, others have an open back so the tower can be readily supplied via crane from below, or targeted from behind if it falls to the enemy. Some towers even have a thicker, sloped base to make undermining more difficult.

Dover Castle reveals another striking difference in tower design – geometry. Originally, castle towers were predominately square. Unfortunately, this configuration leaves the structure vulnerable in areas that archers can’t cover. In the 12th century, medieval engineers begin to design circular and semicircular towers to solve this problem. Because it was built over several decades, Dover boasts square and circular towers – the former being attributed to construction under Henry II, the latter believed to have been built several years later by his son John. The castle also has polygonal towers, including the Avranches Tower, which was specifically designed to maximize the garrison’s firepower.

Motion Comic


Dover Castle’s motion comic reveals the bloody rise of Prince Louis of France, the man who swept across southeast England, determined to lay claim to Dover … and the English throne. The castle’s build, as well as this siege, is profiled in Battle Castle Episode 3: Dover Castle. This comic contains stylized violence.

History Makers