In 1949, Mann married Margaret Hildegarde Marshall Clark, elder daughter of Colonel William Marshall Clark , having three sons and one daughter. Mann lived at Great Farm on the
West Woodhay estate with his wife who predeceased him in 1995, and died on 8 August 2001 at
Stockcross,
Berkshire. Their eldest son,
Captain Simon Mann (
ex-SAS), was sentenced for thirty-four years in
Equatorial Guinea in 2008, on charges related to an
attempted coup in 2004, before being pardoned on 2 November 2009. ==Honours==