district, administrative county of East Sussex, historic county of Sussex, England. Rother is a mainly rural district in the easternmost part of Sussex surrounding (but not including) the borough of Hastings. It extends along the English Channel coast for 23 miles (37 km) and includes the ancient ports of Winchelsea and Rye and the site of the Battle of Hastings (1066). Bexhill is the administrative seat. The district is named for the River Rother, which rises in the Weald, flows east along part of the boundary between East Sussex and Kent, and enters the Channel at Rye. Area 197 square miles (510 square km). Pop. (2001) 85,422.