[45] On these see Mommsen, _Res Gestae_, p. 130 ff.; Gardthausen, _Augustus_, I, p. 1181 ff., II, p. 779 ff.; Domaszewski, _Geschichte der römischen Kaiser_, I, p. 222 f. The Dacians seem to have given provocation in every instance, and even in 11 A. D. once more invaded the empire, though we know nothing about a retaliatory campaign in Dacia on the part of the Romans upon this occasion; cf. Mommsen, _op. cit._, p. 132.
[46] Cf. M. Bang, _The Cambridge Mediaeval History_, 1911, vol. I, p. 195.
[47] An historical study of the buffer or allied state, as a device to strengthen a frontier, would be a profitable one to undertake. There seems to exist no comprehensive treatment of the phenomenon.
[48] See H. R. Hall, _The Ancient History of the Near East_, London, 1913, p. 466, for a brief statement of the facts. For the idea of a buffer state in this connection, compare E. Klamroth, _Die wirtschaftliche Lage und das geistige Lehen der jüdischen Exulanten in Babylonien_. Diss. Königsberg, 1912, p. 20, n. 4.
[49] For the events compare Hall, _op. cit._, p. 543 ff.; for the interpretation in terms of a buffer state, Klamroth, _op. cit._, p. 20. See Appendix, Chapter IV, note 49.
[50] We accept upon this point B. Niese’s convincing arguments, “Neue Beiträge zur Geschichte und Landeskunde Lakedämons”, _Nachr. d. Götting. Ges. d. Wiss._, 1906, p. 101 ff., esp. pp. 131-7.
[51] See J. G. Droysen, _Geschichte des Hellenismus_, I, 2, p. 163 ff. This interpretation of events is much more plausible than that of J. Kaerst (_Geschichte des hellenistischen Zeitalters_, I, p. 369, and n. 2), who argues that the kingdoms of Taxiles and Porus were actually parts of the empire. J. B. Bury (_A History of Greece_, 2nd ed., 1913, p. 807) very properly maintains the position taken by Droysen.
[52] _The Romanes Lecture: Frontiers_, Oxford, 1898, p. 38.—J. Geffcken: _Kaiser Julianus_, 1914, p. 117 uses the expression “Pufferstaat” in speaking of Armenia.
[53] The most elaborate recent study of the policy of Augustus towards Armenia is by A. Abbruzzese, “Le relazioni fra l’impero romano e l’Armenia a tempo di Augusto”, _Riv. di storia antica_, VII (1903), pp. 505-21; 721-34; VIII (1904), pp. 32-61 (also separate, Padova, 1903). His attitude towards the diplomatic policy which Augustus followed is, however, hypercritical, and his thesis that a policy of economic absorption should have been followed is illusory. (Cf. De Sanctis, _Riv. di filol._ LIII (1905), p. 159 f.). A fairly satisfactory statement, though somewhat superficial, is P. P. Asdourian’s dissertation, _Die politischen Beziehungen zwischen Armenien und Rom von 190 v. Chr. bis 428 n. Chr._, Venedig, 1911. His statement, p. 79, of the policy of Augustus as one that attempted to maintain the controlling position in Armenia by peaceful means, or through political manoeuvers, is correct enough, but the sneering remark that this was due not to Augustus’ own inclination, but rather to the rivalry of Parthia is quite superfluous. Of course Rome’s relations to Armenia would have been quite different had there not been a powerful Parthian monarchy. In the mutual rivalries of Rome and Parthia lay the whole difficulty. The best general statement of the problem in its large outlines is in V. Chapot, _La frontière de l’Euphrate_ etc., p. 377 ff. He also can make nothing out of Abbruzzese’s “lotta commerciale” theory (p. 382, note). Mommsen’s statement (_Röm. Gesch._, V, p. 370 ff.) of the general course of Augustus’ Armenian policy is admirable.