The football pitch is a much better dating proposition,as it proves conclusively,that the Ancient Romans who built the circuit walls as one of the Forts of the Saxon Shore,played football,in their spare time.
Larry, considering the castle has been there about 900 years, and was occupied until recently. This cemetery would not be big enough for all the people who died while living in the castle. A quick look at the gravestones show that the earliest graves were in the 1800's.