Not just castrated, erected and penis and testicles removed with a sword. God I know too many things I wish I didn't.
I also would comment as to why I think they enlarged genitals, it's probably the same reason that many African tribes and Pacific Islanders had giant phallic totems of worship, people are superstitious and retarded. Genitals, in general, were seen as a source of mystical power, some more gravitating towards female genitals and some more towards males. In fact, alot of the separation of sexes stuff came from the notion of hypnotic powers women could use to control or manipulate men magically and thus an inherent fear of their mystical nono part powers.