One of my favorite books growing up was "Space Wars: Worlds & Weapons", not so much the text, but the captions to the classic sci-fi art describing a vast and ancient galactic civilization. I have never read anything since that was even close to being so rich in detail (probably because the captions knitted together almost the entire body of science fiction through the 1970s into one universe).
Has the continuity described in the captions ever been developed elsewhere? I would guess not due to the host of potential copyright issues. But if not, has anyone developed something comparable in a book length setting? The closest I can think of is the Terran Trade Authority books or the Third Imperium in the classic Traveller role playing game, but those were not novels...
