Three white seaxes (short Saxon swords) on a red field were the arms ascribed in the later mediaeval period to the ancient Saxon kingdom of Essex. This emblem has been associated with the county for centuries and long before the establishment of local government. The council later established to administer Essex was accordingly granted arms incorporating the ancient seaxes but having thus existed before the origin of the county council, these arms could not be restricted to its use alone and citizens of the Essex have always been free to bear a flag with these ancient seaxes. The flag was duly included in the Flag Institute’s registry upon its creation, as a “traditional” design.

The seaxes of Essex were also used in Middlesex which originally formed part of the early Essex kingdom.

The Essex Kent and Sussex emblems were notably featured in the celebrated county atlas produced by John Speed in 1611 on a map depicting the Anglo-Saxon kingdoms.