I recently found this video series in the creators thread at the EN World forums, and I think it’s something that should really be shared around more.
- Original D&D (1974); 45 min.
- Greyhawk Supplement (1976); 58 min.
- Basic Edition (1979); 38 min.
- Advanced Dungeons & Dragons, 1st Ed. (1978); 69 min.
Despite the title, it’s not just about creating a 1st level human fighter (as the lengths might indicate), but he also goes into detail about a good deal of other parts of the game and how they change over time. As someone who started with D&D in 1999, a lot of things on the older editions have always struck me as really weird or nonsensiscal, but they are not actually that silly when you hear them explained in context. And some are actually quite cool, once you understand what the creators had in mind. (As I frequently mention, TSR D&D was just horribly bad at explaining things to new readers.)