The castrati were male choral singers who had been castrated in order to keep their voices high. Even though this practice sounds barbaric to us, the castrati were condoned and encouraged by, of all institutions, the Catholic church. The Church interpreted certain biblical passages as prohibiting female singers in church, and yet the increasingly-complex music of the 16th and 17th century demanded musicians with high voices and years of practice. By the time they had the requisite musicianship, boys were losing the high-pitched voices of childhood. Enter the castrati. The first castrati were admitted to the Papal Choir in 1599.

Some sources estimate that during the height of the castrati craze during the 18th century as many as 4,000 boys a year were being castrated in Italy, on the relatively off chance that they would become rich and famous singers. Famous castrati were popular enough to prompt people to follow their careers and wear medallions bearing their portraits, becoming in essence castrati groupies.

Amazingly enough, castrati continued in use in the Sistine Chapel long enough for one of them, Allesandro Moreschi, to be recorded. Moreschi was the director of the Sistine Chapel Choir and lived until 1922.