These include a variety of groups. The Skoptji within Russia are a religious sect, and believe castration is the highest form of spirituality. There are also the famed Castrati who served Catholic Churches as well as Eunuchs who served Mid-Eastern harems. Throughout history there have also been a number of individuals who performed self-castration or sought it for personal purposes. Reasons for castration are numerous.
Some males are happy with their relationships, but have an overly active libido.
In other words they feel a sexual compulsion or drive which is so high it interrupts their quality of life. Other males have developed a body dysmorphic condition and feel extremely unhappy with the look and feeling of having testicles. There are also some males who seek castration for spiritual purposes as I previously mentioned. The preceding information highlights some of the more common reasons males seek castration. However in the world of human diversity there are other reasons as well.