The List (notitia) of all high offices (dignitatum), both civil and military, in the Eastern (Oriens) and Western (Occidens) parts’ of the Empire, preserved only in the form of a copy made in 1551, of an original manuscript, now lost, which existed in Speir, is a document of unique importance to the study of the distribution of army units along the Eastern Frontier. The list contains the titles of high officials, those of their staff officers, illustrations of military and civil insignia as well as an enumeration of military units and their garrisons. The work is divided into two parts, covering the Eastern and Western halves of the Empire as it was divided in 395. It is generally accepted that the Eastern half of the work was finished before 413 and probably not much later than 395. The disposition of the frontier units in the East reflects the frontier changes after Jovian’s treaty with Shapur in 363 as no units are assigned to fortresses ceded to the Persians in the treaty such as Nisibis, Singara, Bezabde and Castra Maurorum. Nevertheless, many of the units listed in the Notitia would have been in their given bases in the period between Diocletian and Jovian. Epithets such as ‘Diocletiana’, ‘Iovia’, ‘Herculia’, ‘Valeria’, ‘Flavia’ and ‘Constantina’ suggest Tetrarchic or Constantinian origins to their bearers. Similarly, ‘Valentiana’, ‘Valentiniana’, ‘Honoriana’ or ‘Gratiana’ presuppose post-Jovianic dates for the units’ formation. Therefore, despite its Theodosian date of composition, the Notitia is a frequently cited document in any serious study of the military reforms and frontier reorganization from the Tetrarchy onwards and of the historical geography of the frontier regions. Cf. Jones, 1964 (in): 347-80 and Hoffmann, 1969:516-19.