One western holiday that has great significance for all eunuchs is March 24, Dies sanguinis – a day of mourning, fasting and abstinence commemorating the sorrow of the Great Mother of the Gods for Attis. The frenzied dance and self-laceration of the priests in commemoration of Attis' deed, and the submission to the act of consecration by candidates for the priesthood, was a special feature of the day. The “final act of consecration” was their self-castration.

There’s quite a bit of information on the faith centered on the Great Mother of the Gods, also known as Cybele and by many other regional names. A good starting point is the Wikipedia article Great Mother of the Gods (http://en.wikipedia.org/wiki/Great_Mother_of_the_Gods).

Her followers were among the major competitors to early Christianity. (The followers of Mithra were the other major competition.) The Vatican was sited where it is partly to cover the most important of the temples to the Great Mother of the Gods. This would make St. Peter’s Square one of the most sacred places for eunuchs in the world.