This operation became the precursor to GCHQ, which remained in Eastcote after the war until the department moved to purpose-built buildings in Cheltenham in 1952.

Lady Mary Bankes lived in Eastcote for a time, and led the defence of Corfe Castle in Dorset against the Roundheads during the English Civil War.

Eastcote was originally recorded as Ascot, one of the three medieval tithings [a] of the parish of Ruislip, along with Westcot and Norwood.

As a Royalist, she defended their home in Dorset, Corfe Castle, against the Roundheads in 1643 at the time of the English Civil War.

A plaque on the south wall of St Martin's Church in Ruislip commemorates her heroic act.

Lady Bankes had also lived at Haydon Hall in Eastcote, and her name is remembered by the school in Northwood Hills.

[5] The first Haydon Hall was built in 1630 for Lady Alice, the Dowager Countess of Derby, predominantly to allow her to store her possessions there.

Lady Alice lived at Harefield Place, and purchased the land on which the hall was built from the Haydon family.

The family appear in parish records from 1394 until 1562 when they sold a house on the site of Haydon Hall to William Nicholas.

The tea garden of the Old Barn House became popular with visitors to the area, as were cottages including The Rosery and Orchard Farm which served refreshments.

[16] Bletchley Park also established an outpost in surplus buildings on the site, which became known to staff as HMS Pembroke V. A total of 100 Bombe codebreaker machines were used to decode German Enigma messages.

[17] The station closed shortly after the war ended in 1945,[18] although the operations from Bletchley Park were re-established on the site in April 1946, under the new name of "Government Communications Headquarters" (GCHQ).

[19][21] In 1952, a number of new houses were built by Wimpeys Ltd in Newnham Avenue for the Ruislip-Northwood Urban District Council as part of their "no fines" scheme.