Leo Allatius
FREE Catholic Classes
(Alacci).
A learned Greek of the seventeenth century, b. on the island of Chios in 1586, and d. at Rome, 19 January, 1669. He entered the Greek college at Rome in 1600, spent three years in Lucania with his countryman, Bishop Bernard Giustiniani, and then returned to Chios where he proved of great assistance to the Latin Bishop, Marco Giustiniani. In 1616, he received the degree Doctor of Medicine from the Sapienza, was made Scriptor in the Vatican Library, and later, professor of rhetoric at the Greek College, a position which he held for only two years. Pope Gregory XV sent him to Germany, in 1622, to bring to Rome the Palatinate library of Heidelberg, which Maximilian had presented to the Pope in return for war subsidies, a task which he accomplished in the face of great difficulties. In the death of Gregory XV (1623) Allatius lost his principal patron; but with the support of influential churchmen, he continued his researches especially upon the Palatinate manuscripts. Alexander VII made him custodian of the Vatican library in 1661, where he remained till his death. With untiring energy Allatius combined a vast erudition, which he brought to bear upon literary, historical, philosophical, and theological questions. He laboured earnestly to effect the reconciliation of the Greek Church with that of Rome and to this end wrote his most important work, "De Ecclesiae Occidentalisatque Orientalis perpetua consensione" (Cologne, 1648), in which the points of agreement between the Churches are emphasized, while their differences are minimized. He also edited or translated into Latin the writings of various Greek authors, corresponded with the foremost scholars of Europe, contributed as editor to the "Corpus Byzantinorum" (Paris), and arranged for the Publication of a "Bibliotheca Scriptorum Graecorum". He bequeathed his manuscripts about 150 volumes) and his correspondence (over 1,000 letters) to the library of the Oratorians in Rome.
Join the Movement
When you sign up below, you don't just join an email list - you're joining an entire movement for Free world class Catholic education.

Novena for Pope Francis | FREE PDF Download
-
- Stations of the Cross
- Easter / Lent
- 5 Lenten Prayers
- Ash Wednesday
- Living Lent
- 7 Morning Prayers
- Mysteries of the Rosary
- Litany of the Bl. Virgin Mary
- Popular Saints
- Popular Prayers
- Female Saints
- Saint Feast Days by Month
- Pray the Rosary

JUDGES, GUNS, AND GANGS: Cartels Are Infiltrating America’s Cities and Courtrooms

List of 21 California Missions and Founding Dates
Exploring the California Missions and Their Legacy
Daily Catholic
Daily Readings for Sunday, April 27, 2025
St. Zita: Saint of the Day for Sunday, April 27, 2025
Prayer for the Dead # 2: Prayer of the Day for Sunday, April 27, 2025
Daily Readings for Saturday, April 26, 2025
St. Cletus: Saint of the Day for Saturday, April 26, 2025
- Prayer before the Closing of the Day: Prayer of the Day for Saturday, April 26, 2025
Copyright 2025 Catholic Online. All materials contained on this site, whether written, audible or visual are the exclusive property of Catholic Online and are protected under U.S. and International copyright laws, © Copyright 2025 Catholic Online. Any unauthorized use, without prior written consent of Catholic Online is strictly forbidden and prohibited.
Catholic Online is a Project of Your Catholic Voice Foundation, a Not-for-Profit Corporation. Your Catholic Voice Foundation has been granted a recognition of tax exemption under Section 501(c)(3) of the Internal Revenue Code. Federal Tax Identification Number: 81-0596847. Your gift is tax-deductible as allowed by law.