Isleworth is a small town of Saxon origin sited within the London Borough of Hounslow in west London; west of the River Thames and its tributary the River Crane.
The Abbey of St Valeri in Picardy held the livings and revenues of several English parishes and, responding to growing disquiet over these foreign holdings, in 1391 it transferred those of Isleworth (for a fee) to William of Wykeham, who endowed them to Winchester College, which he founded.
The Wardens and Scholars of Winchester College therefore became proprietors of Isleworth Church. This lasted for 150 years, then in 1543 King Henry VIII exchanged with Winchester certain manors elsewhere for five churches in Middlesex, including All Saints.
Four years later he gave the Isleworth rectory and advowson to the Edward Seymour, 1st Duke of Somerset, but got them back again when the Duke was executed in 1552. Soon after, they were given to the Dean and Canons of St George’s Chapel, Windsor, with whom they remain today.