It would be interesting to trace the relationship between the idea of universal moral value, and the idea of universal religion. Moldbug argues that the latter pretty much spawned the former (that's probably a rough approximation), though I don't trust his scholarship on the history of ideas that much. I don't know to what extent the ancient Greeks and Romans and Chinese and Arabs considered their values to be universal (though apparently Romans legal scholars had the concept of "natural law" which they got from the Greeks which seems to map pretty closely to that idea, independently of Christianity and related universal religions).