Reading Sean Howe's MARVEL COMICS: THE UNTOLD STORY reminded me of these books, which were oversized, "bedsheet" books that came out in the early Seventies, published by the author's own company, Supergraphics. They were the first real comics history books I ever read. Surprisingly, I don't remember where I bought them, but I certainly remember reading them.
I was already a fan of Jim Steranko, who did some great, groundbreaking work as writer/artist on the NICK FURY, AGENT OF S.H.I.E.L.D. comic book. Also during this era, he painted the covers for Jove/HBJ's paperback reprints of some of the Shadow pulp novels, which I also read regularly. By the time I found these volumes on the history of comics, I already knew a little about the subject, but not nearly as much as Jim Steranko did.
Even better, Volume 1 actually has a lot in it about the history of pulp magazines, too, also a subject of great interest to me. Volume 1 covers pulps and the so-called Golden Age of Comics, the Forties. Volume 2 is concerned mainly with the late Fifties and the Sixties, known as the Silver Age. Fascinating stuff, great illustrations. I just got lost in these books for days, learned a great deal, and was thoroughly entertained at the same time. Copies are a little pricey these days, but if you're a comics fan and haven't read them, they're probably worth it.
UPDATE: It's been pointed out to me that Volume 2 covers more of the Golden Age, not the Silver Age. My memory has betrayed me again.
Below are the spectacular wraparound covers of both volumes.