The Middle Saxons or Middel Seaxe were a people whose territory later became, with somewhat contracted boundaries, the county of Middlesex, England.
The first known mention of Middlesex stems from a royal charter of 704 between king Swæfred of Essex, the abdicating king Æthelred of Mercia and succeeding king Coenred of Mercia, granting some land to bishop Walhere in Tuican hom (Twickenham) in the provincia called Middleseaxan.
Middlesex (/ˈmɪdəlsɛks/ ; abbreviation: Middx) was one of the counties of England until it was abolished in 1965. The county boundaries largely followed three rivers: the Thames in the south, the Lea to the east and the Colne to the west, with a line of hills forming its northern boundary with Hertfordshire. The former area of Middlesex now lies almost entirely in the ceremonial county of Greater London, with smaller parts in the counties of Hertfordshire and Surrey. The county was the second smallest of the historic counties of England, after Rutland.
The name of the county derives from its origin as a homeland for the Middle Saxons in the early Middle Ages, with the county subsequently part of that territory in the ninth or tenth century. The City of London, formerly part of the county, became a self governing county corporate in the twelfth century; the City was still able to exert influence as the sheriffs of London maintained their jurisdiction in Middlesex, though the county otherwise remained separate. To the east of the City, the Tower Division (or Tower Hamlets) had considerable autonomy under its own Lord Lieutenant. To the west, precincts around Westminster and Charing Cross became built up.
The Kingdom of the Kentish, today referred to as the Kingdom of Kent, was an early medieval kingdom in what is now South East England. It existed from either the fifth or the sixth century AD until it was fully absorbed into the Kingdom of Wessex in the mid-9th century and later into the Kingdom of England in the early 10th century.
Under the preceding Romano-British administration the area of Kent faced repeated attacks from seafaring raiders during the fourth century AD. It is likely that Germanic-speaking foederati were invited to settle in the area as mercenaries. Following the end of Roman administration in 410, further linguistically Germanic tribal groups moved into the area, as testified by both archaeological evidence and Late Anglo-Saxon textual sources. The primary ethnic group to settle in the area appears to have been the Jutes: they established their Kingdom in East Kent and may initially have been under the dominion of the Kingdom of Francia. It has been argued that an East Saxon or Middle Saxon community initially settled in West Kent and merged with the expanding kingdom of East Kent in the sixth century, but this is uncertain.