Database of Religious History
The DRH is a massive, standardized, searchable encyclopedia of the current best scholarly opinion on historical religious traditions and the historical record more generally.
Reference
NAPS-The North American Patristics Society
North American Patristics Society page focused on early Christianity with links to: Encyclopedias Early Christian Texts Oriental Christianity Guides and Bibliographies
Syriaca: The Syriac Reference Portal
Digital project for the study of Syriac literature, culture, and history, with geographical, prosopographical, and bibliographic databases.