On December 3 1778 from Mannheim Mozart wrote to his father To please Herr von Gemmingen and myself I am now composing the first act of the declaimed opera which I was commissioned to write and I am also doing this for nothing; I shall bring it with me and finish it at homeHerr von Gemmingen is the poet of courseand the duodrama is called Semiramis. Nothing else is known of this duodrama. In an 1994 article Laurenz Lutteken believes some of Thamos music originally for Semiramis project.