In his application to the Colonial Secretary to have the play accepted for public performance, O'Flaherty states that the story is 'founded on the records of Navarre'. The play was accepted on 1 August 1842 (State Records of New South Wales CSIL 42/5458).
Further Reference :
First performed at the Royal Victoria Theatre, Sydney, 11 August 1842 (as Isabel of Valois ; Or, The Tyrant of Navarre), for the benefit of Mrs O'Flaherty (and written expressly for that occasion).
Cast included Eliza Winstanley.
