Ever since man stopped wandering and settled in one place, defences were needed. The simplest defence of a settlement was a fence or palisade. Then a ditch and embankment were added. This was exactly the same with castles. The buildings surrounding the castle gatehouse were likewise surrounded by a wall and ditch, making the barbican.
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| Motte-and-bailey castle showing outer palisade and ditch (castlesworld) |
The outer fortifications served two main purposes: Protecting the buildings surrounding the castle and making it harder to attack the castle gatehouse, which was the weak point in the castle defences. Any army would have to breach the barbican and cross to the gatehouse before attacking the castle proper. The barbican also provided a safe area where troops could mass before venturing out.
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| (castlesworld) |
Around 1260/70 an engineer or master mason came up with the idea of making the access to the gatehouse through a right-angle turn. This created a bottleneck forcing attackers to bunch up and providing plenty of opportunity for the defenders to attack them.
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| Barbican into Beaumaris Castle (pinterest) |
Over time, the passageway barbican became popular, and by the 14th century was the norm. It was an extension of the right-angle turn idea, forcing attackers into a narrow passageway where they could be attacked from the parapets on top of the walls. It was essentially a fortified extension to the gatehouse.
Ann Marie Thomas is the author of four medieval history books, a surprisingly cheerful poetry collection about her 2010 stroke, and the science fiction series Flight of the Kestrel. Book one, Intruders, and book two Alien Secrets, are out now.Follow her at http://eepurl.com/bbOsyz