This wiki is a place for everything related to Dungeons & Dragons. There are however a number of other wikis that are specific to certain campaign settings, namely Eberron Wiki, Forgotten Realms Wiki (which also includes Al-Qadim articles) and Spelljammer Wiki at Wikia, as well as the Great Library of Greyhawk at Canonfire.
Topics that are related to one of those campaign settings only, are likely to be maintained in more detail a the respective wiki. Therefore, such topics should have articles with some basic information that should be enough for a non-excited reader to get the basic idea here at D&D wiki, and include a link to more detailed articles in more specifc wikis. For examples see Kor or Flanaess.
A good starting point to find out which topics are already covered at campaign setting-specific wikis are the Lists of D&D articles from other wikis.