Cross-searchable database of books, articles and reviews, which contribute to the study of Gnosticism and early Christianity.

Offers unrivalled coverage of medieval Church prelates, information on all 1300 medieval bishoprics, archdioceses and patriarchates under obedience to Rome. As of 2003, it provides prosopographical information on 18,507 bishops, archbishops and patriarchs.

The Monastic Matrix is an ongoing collaborative effort by an international group of scholars of medieval history, religion, history of art, archaeology and other disciplines, as well as librarians and experts in computer technology to document the participation of Christian women in the religion and society of medieval Europe. In particular, to collect and make available all existing data about all professional Christian women in Europe between 400 and 1600 C.E.

A database documenting the careers of all Church of England clergymen between 1540 and 1835. This website not only gives access to the Database, but also provides a range of supporting materials about the Church and its clergy.

Sacramentum Mundi Online is the online edition of the famous six volume English reference work in Catholic Theology, edited (in 1968-1970) by Karl Rahner, one of the main Catholic theologians of the 20th century.

Online version of the 3rd edition of the World Christian Encyclopedia, which documents the changing status of World Christianity over the past 120 years from historical and social scientific perspectives. It records the continued shift of Christianity to the Global South and contains estimates for religious and nonreligious affiliation in every country of the world, including detail on Christianity to the denominational level.