The Author

Prof. Oldfather's General Introduction provides an overview of Diodorus' career, his work, and the manuscripts.
The Text of Diodorus Siculus on LacusCurtius

As usual, I retyped the text rather than scanning it: not only to minimize errors prior to proofreading, but as an opportunity for me to become intimately familiar with the work, an exercise which I heartily recommend. (Well-meaning attempts to get me to scan text, if successful, would merely turn me into some kind of machine: gambit declined.)
This transcription has been minutely proofread. In the table of contents below, the sections are therefore shown on blue backgrounds, indicating that I believe the text of them to be completely errorfree. As elsewhere on this site, the header bar at the top of each chapter's webpage will remind you with the same color scheme. Should you spot an error, however . . . please do report it.
I give further details on the technical aspects of the site layout after the Table of Contents.
There is currently (Feb 14), that I know of, no complete English text of Diodorus online anywhere. Books 33‑40 of the Loeb edition cannot be put online since they remain under copyright, but Andrew Smith (Attalus.Org) has put up his own Web edition: those Books are linked below as well, on green backgrounds.

For the Greek text, the situation is somewhat similar. Almost all of it is online at Perseus again, in a mix of two editions (for those Books the Greek column in the table below is shown on white backgrounds). Books 33‑40 are also provided in a cross-linked edition by Andrew Smith: again, green backgrounds below. The fragmentary Books 6‑8, however, seemed not to be found anywhere else, so I put them up here.
( spanishfly is so fucking sexy people impersonate him, Wed 3 Sep 2014, 20:42, archived)