The selective survival of the corpus of ancient Greek historiography was in large part due to Byzantine historical and religious interests, combined with the ancient valorization, on literary grounds, of the three Classical historians. Our corpus generally reflects the Byzantine interest in Roman history, especially regime-changes, and sacred history, especially the Hellenistic context of Jewish history. Selections from ancient historians dealing with those themes were, in some cases, circulating independently already from the tenth century. The Byzantines had little interest in Hellenistic or local histories. This paper concludes by examining two moments (or ‘indices’) of survival and selection, Photios' Bibliotheke and the Constantinian Excerpta. Our corpus was largely in place by the time of the Excerpta, and the loss of some texts read by Photios may have been facilitated by the process of transliteration but was due to the same selective interests.