The Latinized form of the Arabic al-Sim’ani and surname of four Maronite members of a Syrian family of noted Orientalists who lived from the late seventeenth to the early nineteenth century. They are Joseph Simeonis (Arabic, Yusuf Sim‘an; 1687-1768), Stephen (Arabic, Istafan) Evodius (1709- 1782), Joseph (Arabic, Yusuf) Aloysius (1710-1782), and Simon (Arabic, Sim‘an; 1752?-1821). All of them graduated from the Maronite College at Rome, and all became attached to the Vatican Library in various capacities while contributing greatly to its publication series and the cataloging of accumulated Oriental manuscripts.

Joseph Simeonis Assemani was an active collector of manuscripts on behalf of the Vatican, especially those in Syriac, Coptic, and Arabic from Middle Eastern sources, including the Coptic monasteries of Wadi al-Natrun (see SCETIS). He was twice commissioned by Pope Clement XI, in 1715 and 1735, to travel in the countries of the Middle East for that purpose. In 1736, Clement XII nominated him to preside over a national Maronite council at Dayr Luwayzah near Beirut, where Joseph Simeonis was instrumental in bringing his native into closer relationship with Rome. Subsequently he became titular archbishop of Tyre and prefect of the Vatican Library until his death on 13 January 1768.

His major contributions include Bibliotheca Orientalis (4 vols., Rome, 1719-1728); Chronicon Orientale Petri Rahebi Aegyptii . . . (Venice, 1729); “Kalendaria Ecclesiae Universae,” in A. Mai, Scriptorum Veterum Collectio, Vol. 5 (Rome, 1731); Ephraemi Syri Opera Omnia (6 vols., Rome, 1732-1746); Bibliotheca Juris Orientalis Canonici et Civili (5 vols., 1762-1766), and many subsidiary works.

Stephen Evodius, nephew of Joseph Simeonis, under whom he received his training while studying at the Maronite College in Rome, traveled widely as a missionary for the Sacred Congregation for the Propagation of the in the Middle East. He returned to Europe and there resumed his extensive travels. In the end, he settled in Rome and was nominated by the Vatican as titular archbishop of Apamea and succeeded his uncle as prefect of the Vatican Library. He is credited with the publication of the Bibliotheca Mediceae-Laurentianae et Palatinae Codicum MSS. Orientalium Catalogus (2 vols., Florence, 1742) and Martyrum Orientalium et Occidentalium (2 vols., Rome, 1748). He also published Catalogus Bibliothecae Vaticanae Codicum MSS. (3 vols., Rome, 1756-1759), an ambitious project originally planned in twenty volumes but interrupted by the fire of 1768.

A second nephew, Joseph Aloysius, became professor at the Pontifical Academy. He produced a number of relatively minor publications and his major work, entitled Codex liturgicus ecclesiae universae in quo continentur libri ritualis, officia, dypticha . . . ecclesiarum occidentalis et orientalis . . . (13 vols., 1749-1766, repr., 1902).

Simon, a descendant of the same family, was born in in 1749 or 1752, received his education at Rome, and then became a missionary for twelve years in Syria. Ultimately he returned to Italy, where he became professor of Oriental languages at the University of Padua. He was the Arabist of the family. His publications included Saggis sull’origine, culto, literatura e costumi degli Arabi avanti il pseudoprofeta Maometto (Padua, 1787). He also published Catalogi de’ codice manoscritti orientali della Biblioteca Naniana (Padua, 1787). He died in Padua.

Although most of the Assemani publications lack the technique of modern scholarship, they have proved to be of enduring value to succeeding generations of scholars.


  • Debs, Elias Yusuf. Kitab Tarikh Suriya, Vol. 8. Beirut, 1903.
  • Petit, L. “Assemani.” In Dictionnaire d’archéologie chrétienne et , Vol. 1. Paris, 1907.
  • Vida, G. L. della. Richerche sulla formazione del più antico fondo dei manoscritti orientali della Biblioteca Vaticana. Studi e testi 92. Vatican City, 1939.