In the extant writings of certain of the Church Fathers there are some interesting references to a man named Thallus. At the present time, beyond what can be inferred from these early Christian references, nothing is certainly known about him. In recent years, however, attempts have been made to fix the identity of this Thallus. Because of its potential significance for the early history of the gospel tradition, one of these attempts has become rather popular. Much of the acclaim over this suggested identification would seem to be based on a confusion between what has recently been said about Thallus and what is actually known about him from the early Christian references. Consequently, numerous errors of fact and fancy have arisen. It is the purpose of this paper to investigate, first, what is actually known about the Thallus referred to by the Church Fathers, and second, the validity of the identification currently proposed.