Thanks, Fred, that is helpful. I had read a number of sources that matter-of-factly framed Taoism originally as a philosophy that later became a religion; likewise, similar tracts stated that Buddhism was first a philosophy in the hands of Siddhartha, but acquired a lot of deities and cosmic beings, along with layers of ritual complexity, as it was adopted by various cultures that included their earlier belief systems. Do you know whether this is accurate or not, as well? Any suggested reading?
I'll look at the shelf tonight. It's certainly the case that Buddhism was originally aniconographic
and the development of an extensive iconography of deities, cosmic beings, and associated ritual practices (which was really a sort of adoption and re-valuative transformation of those entities and practices and their roles within the context of Buddhist thought). One of the longest strands of this kind that one can tease out is the Homa (or Goma) Fire rites, which are found throughout East Asian Buddhism and which can be traced all the way back to pre-Buddhist Vedic practices which were restricted to the Brahmanic class in India. One essential work that covers much of this is Tantric Buddhism in East Asia
, edited by Richard Payne.
It's true that there were many "religious" ideas that the Gautama Buddha deemed irrelevant as "questions not tending to provide answers that relieve suffering." To follow on NagaBaba's notes above, there is pretty firm evidence that the Gautama Buddha studied a number of yoga systems (all of which he found lacking in one way or another). Does this mean they were necessary parts of his development to be emulated or dead ends which he exited? Buddhists disagree. Do deities exist? Buddhists disagree.
What Buddhists agree on is that deities, like everything else, have no inherent existence. Most Buddhists engage in a variety of ritual practices, some involving "deities," some not, some simple, some terrifyingly complex, to study the nature of existence and their response to it as sentient beings. So what makes a religion? The theory or the practice? The drapes or the windows?
What I would argue is that one has to be very selective about criteria to get an absolutely unequivocal answer to the question: Is Buddhism a religion? Which is a good place to mention Nagarjuna's tetralemma.....
The "non-religious" Buddhism of the 20th Century is, in many respects, a sort of curious variant which arose out of the work of Col. Henry Olcott and a bunch of jackleg Theosophists, the Fifth Buddhist Council (held in Burma in 1871, ostensibly sponsored by King Mindon, but actually underwritten by the British, who were trying to drive a wedge between the Buddhist communities of East Asian on the one hand, and Southeast and South Asia on the other. In the same period, British diplomat-scholars also tagged Tibetan and Mongolian Buddhism as "Lamaism" and denied that it was Buddhist in anything but the most degenerate possible sense.), the subsequent revaluation and re-introduction of all of the above to American popular culture by the Beats, and then a reimportation of the variant to the East.
Fascinating stuff, but not the place to go if you're looking for clean-cut distinctions.