Dereham, also known historically as East Dereham, is a town and civil parish in the Breckland District of the English county of Norfolk. It is s…Dereham, also known historically as East Dereham, is a town and civil parish in the Breckland District of the English county of Norfolk. It is situated on the A47 road, about 15 miles west of the city of Norwich and 25 miles east of King's Lynn.