The Lausiac History (Historia Lausiaca) is a seminal work archiving the Desert Fathers (early Christian monks who lived in the Egyptian desert) written in 419-420 by Palladius of Galatia, at the request of Lausus, chamberlain at the court of the Byzantine Emperor Theodosius II.
The book was popular among monks all over the East, who appear to have added to it considerably in transcribing it. The first edition was a Latin version by Gentian Hervetus. A shorter Greek text was published by Johannes Meursius (Leyden, 1616), and a longer one by Fronton du Duc, and a still more complete one by J. Cotelerius. This longer version contains the text of Rufinus. Butler, Preuschen, and others think that the shorter text (of Meursius) is Palladius's authentic work, the longer version being interpolated. Amélineau holds that the longer text is all Palladius's work, and that the first thirty-seven chapters (about the monks of Lower Egypt) are mainly an account of what the author saw and heard, though even here he has also used documents. But he thinks the second part (about Upper Egypt) is merely a compilation from a Coptic or Greek document which Rufinus also used; so that Palladius's visit to Upper Egypt must be a literary fiction. But the shorter text itself exists in various forms. A Syrian monk, Anan-Isho, living in the sixth-seventh centuries in Mesopotamia, translated the "Lausiac History" into Syriac with further interpolations. At one time the "Lausiac History" was considered a compilation of imaginary legends. Roman Catholic scholars at the beginning of the twentieth century argued that it was also a serious source on Egyptian monasticism, in between the miracles.
In the Orthodox Church (the Byzantine Rite) the Lausiac History is read at matins on the weekdays of Great Lent as two of the patristic readings, after the third kathisma and after the third ode of the canon.