 Complete the following phrase:  Owing to its proximity to London, Berkshire has from early times been the scene of frequent military operations. The earliest recorded historical fact relating to the county is the occupation of the district between Wallingford and Ashbury by Offa in 758. In the 9th and 10th centuries the county was greatly impoverished by the ravages of the Danes, and in 871 the invaders were defeated by Æthelwulf at Englefield and again at Reading. During 