The name Constantinian Excerpts refers to an assemblage of the works of ancient and early medieval historians commissioned by Constantine VII Porphyrogenitos (945– 959). Originally arranged into fifty- three volumes on a number of topics, now only “On Embassies” exists in its entirety, along with parts of “On Virtues and Vices,” “On Ambushes,” and “On Gnomic Statements.” These are often known by their modern Latin titles: de legationibus, de virtutibus et vitiis, de insidiis, and de sententiis. Each extant volume includes the same preface, the text of which explains that the project was intended to make the vast amount of historical knowledge more intelligible and accessible.

The point of the project apparently was not to excerpt the useful information from longer histories, but rather to rearrange all of those histories by topic. Because history was thought to be useful to emperors due to the lessons it could teach, Constantine's project reorganized history by problem or lesson rather than by chronology. The compilers organized the material by topic, so that if an emperor was concerned with an upcoming embassy, for example, he could read all the examples of embassies in Roman history at one time, rather than examining the histories in chronological order. The preface explicitly rejected summarizing events in favor of keeping the literary expression of the original texts. It also explains that “nothing contained in the texts would escape this distribution into subjects; by this division according to the content nothing of the continuous narration is omitted, but rather it is preserved entire.” The project was part of a cultural trend in the tenth century toward the collection and arrangement of ancient knowledge.

The project was initiated under the sponsorship of Constantine VII (945– 959) but may have been completed in the decades after his death. Twenty- six histories written in Greek between the fifth century BCE and the ninth century CE are included in our remaining sample. The original may have represented more texts. Many fragments of ancient histories are available only in the remaining Constantinian Excerpts, most notably much of Polybios.