The voice types and character descriptions are taken from the text set to music in 1729 by Leonardo Vinci:[1]
Semiramide (soprano), Assyrian queen, in masculine dress under the name Nimrod; in love with Scitalce, who had previously known her in Egypt under the name Idreno
Mirteo (soprano), Egyptian prince, brother of Semiramis (though he does not know this), in love with Tamiri
Ircano (contralto), Scythian prince, in love with Tamiri
Scitalce (contralto), Indian prince, in love with Semiramide
Tamiri (soprano), Bactrian princess, in love with Scitalce
Sibari (tenor), confidante of and secretly in love with Semiramide