Mozart was fourteen when he wrote Mitridate, re di Ponto for the Teatro Regio Ducale in Milan, where it was first performed on 26 December 1770 and repeated twenty-two times. The commission followed the family's first Italian tour; Vittorio Amedeo Cigna-Santi's libretto derives from Racine's Mithridate. Mozart rewrote arias on demand as the singers arrived and rejected what had been drafted for them. The opera follows the conventions of opera seria exactly — exit arias, da capo forms, a castrato in the second male role — and its interest lies in how completely a boy had absorbed a form he had only recently encountered.