It's funny I almost used Brahma, Vishnu and Shiva but I couldn't find any evidence that showed them passed from one culture to the next. Babylon was the start of false religion and pretty much most cultures post-flood so obviously in one way or another it was passed on to them, if you find the connection I would love to hear it. I find the study of religion very intriguing! One book that is a source for some of this is "mankind's search for God" but a lot of it comes from snippets of other books. I've spent all my life studying these subjects so it's a collection of sources. I did Google a lot of it to double check my work for accuracy.
RE: What is the origin of the Trinity?