Historia ecclesiastica tripartita

The Historia ecclesiastica tripartita is an abridged history of the early Christian Church in twelve books, which became the standard manual of Church history in medieval Europe. It is dated to around 550 AD and consists of a compilation of church histories, parts of which were selected by Cassiodorus and translated into Latin by Epiphanius Scholasticus.

The work condenses three Greek church histories of the previous century: those of Socrates Scholasticus, Sozomen and Theodoret. An Italian theory held that it was composed around 510 AD using the library Cassiodorus assembled at the monastery of Vivarium; it is now thought more likely to have been written several decades later, in Constantinople, around 550, at the time of the crisis between Justinian and the Western Church. It narrates the history of the Church from 324 to 439.

The book earned a high reputation. Only Eusebius' History, in Rufinus' Latin translation, competed with it as the official version of church history in the West, until humanist scholars of the fifteenth century began to rediscover, edit and print the original sources.