Historic county, southeastern England, situated along the River
Thames. Its earliest settlements date from 500 ; Belgic tribes arrived in the 1st century , followed by the Romans, who established outposts along the river. It was colonized by
Saxons in the early 5th century . Situated between the East and West Saxons, it obtained its name (meaning middle Saxons) by 704. Middlesex was established as an administrative county in 1888. In 1965 Greater London incorporated parts from the former county.
For more information on Middlesex, visit Britannica.com.