Collectio Thessalonicensis

Title	Collectio Thessalonicensis
Key	?
Alternative title	Sammlung der Kirche von Tessalonich (Maassen)
Wikidata Item no.	Q114235508
Century	saec. VI
General region of origin	Southern Europe and Mediterranean
Main author	Christof Rolker

The Collectio Thessalonicensis is a small canonical collection containing papal and imperial letters concerning the church of Illyricum, only fragments of which are extant.

The collection is said to have been presented by Greek bishops at a (otherwise unrecorded) Roman synod of 531 to prove the jurisdiction of the Roman Church in Illyricum. The collection survives only in a ninth-century manuscript (Vat. lat. 5751, fol. 55-75) as part of the synodal records, and even here it is only fragmentary. However, there are several references to use of the collection in the 8th and 9th centuries by popes and councils, and Lukas Holstenius may have known of a more complete manuscript than Vat. lat. 5751.

In its extant, fragmentary version, the collections contains 24 letters of the popes from Damasus (366-384) to Leo I (440-461), as well as an exchange of letters between the emperors Flavius Honorius and Theodosius II (after 421) and two letters to Pope Leo I. One of pieces, a rescript of Theodosius II, was proven to be a forgery by Theodor Mommsen. The complete version of the Thessalonicensis seems to have contained letters of other popes from Hilarius to Hormisdas.

Lukas Holstenius published the editio princeps in 1662 under the title Collectio Romana bipartita. The Ballerini renamed it Collectio ecclesiae Thessalonicensis. Karl (von) Silva-Tarouca S.J. presented a critical edition in 1937 and used the title Collectio Thessalonicensis, which is still in use today.