The version I saw was the 1970s one--ironically enough, the one episode I remember distinctly is the Alamo...and it's the one on YouTube! (Intro/outro only, unfortunately).
I missed the seventies version; I was more familiar with the earlier version, not from TV, but from the films distributed to schools. At least in the school systems I attended, it was the only decent (and interesting) teaching of history ever attempted.