PERCEPTIONS AND REALITIES
If there was one author who transmitted his own personal perceptions about the problems of the frontiers of the Roman Empire (i.e. fines, limites imperii) in the fourth century A.D., it was the anonymous author of the small pamphlet known as De rebus bellicis.1 This short treatise does not belong to the official historiography of the period—a fact of great interest for our purpose. It expresses or, better, reflects the author's personal vision of the problems, without the interference of official rhetoric. He recommends to the Emperor (surely Constantius II and his colleague, the Caesar Julian)2 a series of measures that should be taken for the welfare of the Empire. Most of them are military, defensive measures, but they are not only that, for there are also fiscal strategies. Both are inextricably united or mixed. In fact, two centuries before, the historian Tacitus formulated a strict correlation between the military and the fiscal, showing their inexorable connection: the greater the number of armies needed, the greater the expenses in stipendia; the greater the stipendia, the more taxes that will, inevitably, fall upon the provincials: neque quies gentium sine armis; neque arma sine stipendia, neque stipendia sine tributis.3 Thus Tacitus.
1 There are, of course, other writers in the fourth century who were conscious of the
problem of frontiers and expressed their opinion about them—Ammianus and Themistius
are two examples (I would like to thank Peter Heather for drawing my attention to
Themistius Oratio 8, p. 170, 113 ff., which expresses almost the same opinion as the
Anonymus, De rebus bellicis: even so, the context of a speech delivered to the Emperor,
with all its rhetorical conventions, is of less value, in my opinion, than the spontaneous
and imaginative booklet of the Anonymous). On Ammianus about frontiers see
J. Matthews, The Roman Empire of Ammianus (London, 1989), with full references and
bibliography. For the Anonymous' De rebus bellicis I have used the edition of Andrea
Giardina, Le cose della guerra (Milan, 1989), but R. Ireland, De rebus bellicis, Part II, The
Text, BAR Inter. Series, LXIII (1979) and E.A. Thompson, A Roman Reformer and Inventor,
Being a New Text of the Treatise De Rebus Bellicis (Oxford, 1952) should also be mentioned.
2 The discussion about the date and addressee of the anonymous has been a long
one: Giardina offers a good summary of it on pp. xxxvii–lii, and I follow him in his
proposal—i.e. Constantius II and the Caesar Julian.
3 Tacitus, Hist. IV, 74.