The project began with the “Auslandsschreiben” (letters to potentates abroad) of the Byzantine imperial chancery during the dynasties of the Komnenoi and Angeloi (11th and 12th centuries) and was later extended, on the one side to the period of Palaiologoi, on the other to the eight and ninth centuries. It focuses on a critical edition of all letters, agreements and contracts with potentates abroad issued by the Byzantine imperial chancery. This editorial work is accompanied by detailed studies on related historical or diplomatic questions. Additionally, photographs of all available documents have been collected, partly in co-operation with the photographic archive at the Bavarian Academy of Sciences, Commission for the edition of the Corpus of the Greek documents of the Medieval and Modern Times.

For the interpretation of the documents new methods of historical sociolinguistics and textpragmatics are used such as variations between impersonal imperial formulas and the personal pronouns of the first person plural or singular in order to express proximity or distance to the addressees (Initial 2 [2014] 79–105). A further research focus is on translations and translators of the imperial chancery in the correspondence with the West (Latin department) as well as on the Latin documents of the Palaiologan period.

The (original) documents are analyzed in the context of the related research project of the Greek copyists, also under palaeographic and codicological aspects.

New discoveries about Byzantine imperial (and patriarchal) documents were published with photo documentation in the Jahrbuch der Österreichischen Byzantinistik 70 (2020) (from the time of the Council of Basel and Ferrara).