It was customary in the middle ages for the church to castrate choir boys so their tenor voice would not change. That way they could maintain the integrity of boys choirs popular during the middle ages and beyond. There is an official category of voice called the "castrato". That is in addition to bass, baritone, tenor etc.

It is a wonder they are not doing that today.

were castrated as a "cure" for homosexuality while in Catholic run psychiatric hospitals.

Two clergymen were convicted of abuse but Mr Heithuis, a victim, was nonetheless transferred by police to a Catholic psychiatric hospital before being admitted to the St. Joseph Hospital in Veghel later that year.
There, court papers confirm, he was castrated "at his own request", despite no submission of his written consent. Sources told Mr Dohmen that the surgical removal of testicles was regarded as a treatment for homosexuality and also as a punishment for those who accused clergy of sexual abuse.

There are also allegations that Vic Marijnen, a former Dutch Prime Minister, who died in 1975, was linked to the case.
In 1956, Mr Marijnen was the chairman of the Gelderland children's home where Mr Heithuis and other children were abused. He intervened to have prison sentences dropped against several priests convicted of abusing children.

One of the last was a man named Moreschi, the only castrati to make sound recordings, who died shortly after WWI.