Jacobite pretender The longest claimed reign was that of James Francis Edward Stuart the Old Pretender whose reign as King over the Water lasted 64 years 3 months and 16 days as the Jacobite pretender to the thrones of England Scotland and Ireland then to the thrones of Great Britain and Ireland 17 September 1701 1 January 1766 As I misunderstand it the Jacobites consider ed the Act of Union invalid being enacted by an usurper and thus deny that there is a throne of Great Britain so this sentence is a bit like saying a Capetian heir claims the throne of the Fifth Republic