The Diablo 2 Wiki
The Diablo 2 Wiki archive is available for anyone looking for information on Diablo 2. All information here is pre-D2R but contains a lot of useful information that is still relevant. Updated sections for new D2R features can be found on the PureDiablo Diablo 2 section

Great Conflict

From Diablo 2 Wiki

The Great Conflict article is strongly related to Diablo, but not specifically an integral part of Diablo I or Diablo II. Due to the large amount of information that is unique to Diablo I and II versus Diablo III, we have separated them into two wikis. Lore, characters, locations as well as general Diablo information is therefore represented in the main D2 Wiki, where a lot of new information has also been made available after the announcement of Diablo III.

This is such a case, and you can find the full Great Conflict article on the following DiabloWiki page: