When Gaia the Earth of Greek Mythology was sick of her husband Uranus the Sky (who was also her son) ramming their children back into her womb because he hated and feared them, she fashioned a sickle and asked her children to avenge her. The youngest and boldest one, Cronus, then took the sickle, and castrated his father when Uranus let his guard down. Uranus then cursed them with the name "Titans", or "Over-reachers".
The Greeks may have gotten this story from the earlier Hittite myth, in which Kumarbi bites off the testicles of the sky god Anu and gets pregnant from them.
Having murdered his brother Osiris, the Egyptian deity Set dismembered the corpse. This included the severing of Osiris's penis, which was swallowed by a fish before Isis could find it and incorporate it into her late husband's reassembled body.
He got better though after Isis created a new one for him out of ivory.
Adonis of Greek Mythology was caught in a Love Triangle between Persephone and Aphrodite. Aphrodite won, and the jealous Persephone told Ares of Aphrodite's new lover. Ares turned into a boar and gored Adonis in the crotch.
The Fisher King from the Parcival mythos. A spear got him in the hips...groins...whatever. (Your Bowdlerize may vary, see here for details.)