Other than some personal correspondence, there are few sources of information about the non-military parts of Barry's life. The scant available evidence provides a skeleton onto which a great deal of myth and speculation has been added by various commentators. In his detailed research into Barry's early life, Michael Du Preez states that Barry was born in Cork in 1789, a birth date based on Mrs Bulkley's description of her child being fifteen years old in a letter dated 14 January 1805. Various other sources give birth dates of 1792, 1795, and 1799, but these dates are almost certainly the result of Barry later lying about age on official documents to aid passing as a man.