[142] For Phraates and Tiridates, cf. Justin, XLII, 5; Dio, LI, 18. Tiridates had supplanted Phraates and in turn was driven out by him. He then, in 724, came to Augustus for aid. But the latter was anxious to regain the lost standards from Parthia, and simply played off Tiridates against Phraates by setting him over Syria. Dio, in the passage cited, makes mention of a son of Phraates who was captured by Tiridates and given up to Augustus. This was possibly the Phraates here mentioned, though there are difficulties in the way of this explanation. For Augustus implies the voluntary coming of a reigning king, not the delivery of an abducted prince. We know that in 731 Tiridates was in Rome asking that Parthia be assigned to him, and that at the same time Phraates sent an embassy begging the restitution of his son. Cf. Dio, LIII, 33. Augustus laid the matter before the senate, and by their advice restored the prince in exchange for the standards, but did not yield to the plea of Tiridates. [143] Cf. c. 27. [144] A people east of the Tigris, and west of Media Atropatane. Nothing is known of Artaxares. For the Adiabeni and their kingdom, cf. Strabo, XVI, 1, 19; Tac. _Ann._, XII, 13; Josephus, _Ant._, XX, 2, 1. [145] Augustus several times was on the point of invading Britain. Cf. Dio, XLIX, 38, for 720; LIII, 22, 25, for 727, 728. The poets have many prophecies of victories in Britain. Cf. Ver. _Georg._, I, 30, written in 724; III, 25; Hor. _Epode_, VII, 7; _Carm._, I. 35, 29, of the year 727, 728; _Carm._, III, 5; I, 21, 15; III, 4, 33; IV, 14, 48. But nothing came of these plans. Cf. Strabo, IV, 5, 3, for embassies from Britain. Coins of Dumnobellaunus have been found. Cf. J. Evans, _Coins of the Ancient Britons_ (London, 1864), p. 198, and the following plate 4, Nos. 6-12. [146] The great defeat of Lollius in 738 was by the Sicambri, joined with the Usipites and Tencteri. Cf. Dio, LIV, 20; Vell., II, 97; Suet., _Aug._, 23. There was a temporary peace. Cf. Horace, _Carm._, IV, 2. 36; 14, 51. They rebelled in 742, and were put down, first by Drusus and later by Tiberius. Cf. Dio, LIV, 32, 33, 36. In 746 they were completely subjugated and removed into Gaul. Cf. Dio, LV, 6; Vell. II, 97; Suet., _Aug._, 21; _Tib._, 9; Tac. _Ann._, II, 26; XII, 39; Strabo, VII, 1, 3. Probably the coming of Maelo was during this surrender of 746. [147] The Marcomani were a branch of the Suevi. Cf. Tac., _Germ._, XXXVIII; _Ann._, II, 44, 62.