Essex. Essex is a county in the south-east of England, north-east of London. One of the home counties, it borders Suffolk and Cambridgeshire to the north, Hertfordshire to the west, Kent across the estuary of the River Thames to the south, and London to the south-west. The county town is Chelmsford, the only city in the county. For government statistical purposes Essex is placed in the East of England region. There are three definitions of the extent of Essex, the widest being the Ancient County, the more usual being the smaller Ceremonial County and smallest being the administrative county-the area administered by the County Council and which excludes the two unitary authorities of Thurrock and Southend-on-Sea. The Ceremonial County occupies the eastern part of what was, during the Early Middle Ages, the Kingdom of Essex. As well as rural areas, the county also includes London Stansted Airport, the new towns of Basildon and Harlow, Lakeside Shopping Centre, the port of Tilbury and the borough of Southend-on-Sea. Main article: History of Essex Essex had its roots in the Kingdom of the East Saxons, a polity which is likely to have had its roots in the territory of the Iron Age Trinovantes tribe. Essex corresponds, fairly closely, to the territory of the Trinovantes tribe. Their production of their own coinage marks them out as one of one of the more advanced tribes on the island, this advantage is probably due to the Belgic element within their elite. Their capital was the oppidum of Colchester, Britain's oldest recorded town, which had its own mint.The tribe were in extended conflict with their western neighbours, the Catuvellauni, and steadily lost ground. By AD 10 they had came under the complete control of the Catuvellauni, who took Colchester as their own capital. The Roman invasion of AD 43 began with a landings on the south coast, probably the Richborough area of Kent. After some initial successes against the Britons, they paused to await re-inforcements, and the arrival of the Emperor Claudius. The combined army then proceeded to the capital of the Catevellauni-Trinovantes at Colchester, and took it. Claudius held a review of his invasion force on Lexden Heath where the army formally proclaimed him Imperator. The invasion force that assembled before him included four legions, mounted auxiliaries and an elephant corps-a force of around 30,000 men. At Colchester, the kings of 11 British tribes surrendered to Claudius. Colchester became a Roman Colonia, with the official name Colonia Claudia Victricensis. It was initially the most important city in Roman Britain and in it they established a temple to the God-Emperor Claudius. This was the largest building of its kind in Roman Britain. The establishment of the Colonia is thought to have involved extensive appropriation of land from local people, this and other grievances led to the Trinovantes joining their northern neighbours, the Iceni, in the Boudiccan revolt. The rebels entered the city, and after a Roman last stand at the temple of Claudius, methodically destroyed it, massacring many thousands. A significant Roman force attempting to relieve Colchester was destroyed in pitched battle, known as the Massacre of the Ninth Legion. The rebels then proceeded to sack London and St Albans, with Tacitus estimating that 70-80,000 people killed in the destruction of the three cities. Boudicca was defeated in battle, somewhere in the west midlands, and the Romans are likely to have ravaged the lands of the rebel tribes, so Essex will have suffered greatly. Despite this, the Trinovantes identity persisted. Roman provinces were divided into civitas for local government purposes-with a civitas for the Trinovantes strongly implied by Ptolemy. The late Roman period, and the period shortly after, was the setting for the King Cole legends based around Colchester. Originally recorded in AD 527, Essex occupied territory to the north of the River Thames, incorporating all of what later became Middlesex and most of what later became Hertfordshire.