prosopography

The word is drawn from the figure prosopoeia in classical rhetoric, introduced by Quintilian, in which an absent or imagined person is figured forth—the "face created" as the Greek suggests—in words, as if present.

Central to prosopography are the concepts of individuals and groups - or networks.

The "principles which make it a distinct form of historical science" are: "that every piece of historical data should, as far as possible, be related to an identifiable historical person, that multiple identities should not be confused, single identities should not be multiplied and collective identities should always be defined in terms of connections between individuals".
[Magdalino]