Carol Hills, from The World, wrote to ask about historical and cultural differences in the use of religious names. Why, for example, is Jesus widely used as a personal name in Spanish-speaking countries but not in other traditionally Catholic areas? Among Hindus, Carol observes, some names of gods seem to be widely used as personal names (Vishnu, Krishna) while others are not (Brahma, Shiva).
I don't know anything about this topic — at best I can add some additional questions, like why some of the gods of European paganism have survived as reasonably common modern names (especially Diana and Brigit, but also e.g. Apollo, Minerva, Thor) while others apparently haven't (Baldur, Hermes, Hera, Mars, Odin, Poseidon, Zeus, etc.)
So I'm appealing to readers for (pointers to sources of factual) information on this question.