The human voice

At all times, the human voice has been a highly appreciated instrument. In medieval times and the Renaissance to a degree, where music theoretisist of the day believed that all other instruments was just humble imitations of the human voice.
Christian church music was exclusively written for the male voice in all its nuances: bass, tenor, contra tenor and boy soprano. Trained female singers among secular art music were a rare, but much appreciated phenomenon. (1)
In the Muslim societies the singer was often a qayna, a professional female musician.
Folk music was probably performed by both men and women.

(1) Arnulf de St-Ghislain, aprox. 1400, see ‘The Sound of Medieval Singing’ by Timothy J. McGee – pages 25 and 164