Tancred and Sigismunda

Tancred and Sigismunda,
a tragedy by J. Thomson , published 1745 , produced (with Garrick as Tancred) 1752 .

It is based on the story inserted in Lesage 's Gil Blas, iv. iv, in which Tancred, the heir to the kingdom of Sicily, is lured by the cunning Siffredi into accepting with the throne a bride, Constantia, whom he does not love, and abandoning Siffredi's daughter Sigismunda, whom he does. The latter, in despair at her desertion, consents to marry Osmond, her father's choice. But Tancred does not give up his lady-love so easily. He kills Osmond, but not before the latter has fatally stabbed Sigismunda.