text: The Kingdom of the East Saxons (; ), referred to as the Kingdom of Essex , was one of the seven traditional kingdoms of the Anglo-Saxon Heptarchy. It was founded in the 6th century and covered the territory later occupied by the counties of Essex, Middlesex, much of Hertfordshire and (for a short while) west Kent. The last king of Essex was Sigered of Essex, who in 825 ceded the kingdom to Ecgberht, King of Wessex. From 825 Essex was ruled as part of a south-eastern kingdom of Essex, Kent, Sussex and Surrey. It was not until 860 that Essex was fully integrated into the crown of Wessex.
  Extent
  The Kingdom of Essex was bounded to the north by the River Stour and the Kingdom of East Anglia, to the south by the River Thames and Kent, to the east lay the North Sea and to the west Mercia. The territory included the remains of two provincial Roman capitals, Colchester and London.