I never studied any history by any "official" method; but after playing "Age of Empires II" obsessively back in 1997-98, it got me interested in history, and I started to read and read and read ... 
First in libraries, and then (as my financial situation improved) by buying cheap second-hand books and reading more.Some of it even stuck, I hope!
On the other hand, I never got to experience comic books, or play D&D for more than one or two sessions. (There simply aren't/weren't as many D&D groups around here as there are in the USA). *shrug* I think I still have some of my old D&D 2nd Ed books around - not the source material, but I do have these books:
1. "Sages and Specialists"
2. "The Complete Book of Villains"
3. "Of Ships and the Sea"
4. "Arms and Equipment Guide"
They were not bad.
But man, D&D 2nd Ed had waaay too many supplementary books ... I think TSR used to publish them? Do WotC still publish waaay too many supplementaries?