 During the Interregnum , however , squatters had occupied Windsor Castle . As a result , the " King 's house was a wreck ; the fanatic , the <unk> , and the squatter , having been at work ... Paupers had squatted in many of the towers and cabinets " . Shortly after returning to England , Charles appointed Prince Rupert , one of his few surviving close relatives , to be the Constable of Windsor Castle in 1668 . Rupert immediately began to reorder the castle 's defences , repairing the Round Tower and reconstructing the real tennis court . Charles attempted to restock Windsor Great Park with deer brought over from Germany , but the herds never recovered their pre @-@ war size . Rupert created apartments for himself in the Round Tower , decorated with an " extraordinary " number of weapons and armour , with his inner chambers " hung with <unk> , curious and effeminate pictures " . 
