1 History of Liturgical Reform in the Church of the East: Origins – 20 th Century Fr. Andrew Younan 11/25/2020 Introduction It is the purpose of this paper to give a brief history of liturgical reform in the Church of the East, that Apostolic Church originating in Mesopotamia, traditionally understood as founded by St. Thomas and St. Jude Thaddeus (“Mar Addai”). This Church was variously named the Church of Persia, the Nestorian Church, 1 the “East Syriac” Church, 2 and is currently subsisting in its branches called the Chaldean Catholic Church, the Assyrian Church of the East, and the Ancient Apostolic Assyrian Church of the East. 3 Of all these names, only Chaldean is officially mentioned in Canon Law. 4 Each individual period and reform can be treated only briefly, since my purpose is not to give detailed exposition of the history 5 but rather to abstract canonical principles of liturgical reform from the history itself, and especially from the Synodical documents. Similarly, since the documentation of the entire history of the Church of the East is relatively sparse until recent times, this chapter will contain pertinent information about the reforms occurring from the earliest known data and will end in the 20 th Century. The two (!) liturgical reforms finalized in the 21 st Century are both well documented, and will each, therefore, receive a full chapter in my overall thesis. 1 A name practically universally admitted to be a misnomer, though defended oddly by David Wilmhurst, The Martyred Church: A History of the Church of the East (London: East & West Publishing, 2011), 463. It seems odd to name an entire Church after a Greek bishop who was not a member of it, and whose thought (even if orthodox) only represents a small aspect of the totality of that Church’s teaching and life. See the more balanced approach of William F. Macomber, “A History of the Chaldean Mass,” in Worship 51 (1977), 108. 2 Another unfortunate misnomer. See Macomber, “A History of the Chaldean Mass,” 108: “Such names, however, create the erroneous impression that the Chaldean rite is merely another branch of the rite of Antioch, an impression that is without solid foundation in fact and should be discarded today.” 3 For a thorough recent history, see Wilmshurst, 440-447. 4 Canon 28 § 2 of the Code of Canons of the Eastern Churches: Latin-English Edition (Washington, DC: Canon Law Society of America, 1990). 5 Admirably done in several studies already. See especially Bp Sarhad Yawsip Jammo, The Chaldean Liturgy: At the Gate of God (El Cajon, California: Chaldean Media Center, 2014), 29-100.