u/C4rpy88

Built originally as a motte and bailey, Carisbrooke castle survived a French siege during the hundred years war and the sacking of the Isle of Wight - only being broken after a crossbowman shot the French commander. It was later used as a prison for King Charles I after the English civil war, and served as his final residence prior to his execution (slide 8 being his bedchamber).

Portchester Castle (originally Portus Adurni) was built in the 3rd Century by the Romans to protect the South coast of England from pirate raids. After the abandonment of Britannia, Romano-Briton Celtic tribes made the space inside the fort home. The Anglo-Saxons then captured the fort, and used it as a military instillation. The Norman invasion resulted in a large keep being installed, and subsequent English kings expanded the residences around the keep, while retaining the original Roman walls. It is famous as the castle where Henry V gathered his men for their invasion of France and the battle of Agincourt, and as a prison for Napoleons troops, whose graffiti can still be seen on the walls of the keep.