During World War II, the hall and its grounds were used by the American Office of Strategic Studies, an early predecessor of the CIA.

Saboteurs were airlifted to Europe from nearby Harrington airfield where the Carpetbagger Museum commemorates their contributions to the war effort.

The Thornton family lived at Brockhall Hall until 1969 when it was sold to Peter Lee after the death of the last male heir.

Fremeaux was a Huguenot merchant who had been naturalised as a British citizen in 1752 and had through marriage acquired the Cooke estate at Kingsthorpe in 1762.

The house is reputed to be haunted by a white lady - this might be an owner's wife who committed suicide in the 1780s.