A man who stole a dead baby's name and lived as a bogus aristocrat has been unmasked as Charles Albert Stopford III, a US citizen from Florida.
Charles Albert Stopford III had refused to reveal his true identity
Kent Police checks with American authorities revealed that the man who called himself Lord Buckingham had been missing from the US since 1983.
Stopford, 43, was jailed for 21 months in November 2005 for falsely obtaining a passport under his assumed name.
UK and American authorities are deciding what should happen to him now.
His true identity was investigated after the Stopfords, from Clearwater in Florida, told a Sky One television programme they were "100% positive" the mystery man was a missing family member.
It was then confirmed after fingerprint checks were carried out.
Det Sgt Paul Bratton said on Monday: "This whole inquiry has been distressing - for the mother whose dead baby boy's identity he stole, for this man's former wife and his children who have been left wondering who 'Buckingham' really is, and indeed for Charles Stopford's family in America.
Notepaper with the Buckingham coat of arms was found in Stopford's car
"Now his true identity has been confirmed, hopefully this will help them all come to terms with what has happened."
Stopford, who went under the name of Christopher Edward Buckingham for more than 20 years, was arrested as he drove off a ferry in Dover in January 2005.
Immigration officials had alerted the police after checks in Calais, France, revealed his passport had been revoked.
He pleaded guilty at Canterbury Crown Court to making an untrue statement for the purpose of obtaining a passport.
His prison sentence was reduced in January this year to nine months and he was released into the custody of the UK Immigration Service in February.
The real Christopher Buckingham was born in 1962 in Lambeth, south London, but died in West Sussex the following year.