For my own convenience and that of others, here are links to the four volumes of a quite remarkable and still not superseded work of reference for early Church history down to the ninth century:
William Smith and Henry Wace, eds., A Dictionary of Christian Biography, Literature, Sects and Doctrines: Being a Continuation of the “Dictionary of the Bible,” 4 vols. (London: John Murray, 1877–1887):
- Vol. 1 (1877): A–D [Google Books]
- Vol. 2 (1880): Eaba–Hermocrates [Google Books]
- Vol. 3 (1882): Hermogenes–Myensis [Google Books]
- Vol. 4 (1887): N–Z [Google Books]
A century and a half after publication, the entries are obviously not to be treated as up-to-the-minute scholarship. But they were painstakingly researched and provide information about the sources used to ascertain the facts. I know of no other work that provides quick information about so many historical figures. It is therefore extremely useful for “disambiguation,” i.e., figuring out which historical figure named “X” is being referred to (or may possibly be meant) in a source that isn’t sufficiently specific.
For example, whereas the (wonderful) Oxford Dictionary of the Christian Church has articles on seven persons named “Gregory” who lived in the first nine centuries of the Christian era, Smith and Wace have articles on eighty such persons, occupying 72 pages!