The military forces assembled at different epochs by the kings of Syria enable us to estimate the population of their empire. In 537, at the battle of Raphia, Antiochus had under his command 68,000 men;[420] in 564, at Magnesia, 62,000 infantry, and more than 12,000 horsemen.[421] These armies, it is true, comprised auxiliaries of different nations. The Jews of the district of Carmel alone could raise 40,000 men.[422]
The fleet was no less imposing. Phœnicia counted numerous ports and well-stored arsenals; such were Aradus (_Ruad_), Berytus (_Beyrout_), Tyre (_Sour_). This latter town raised itself gradually from its decline. It was the same with Sidon (_Saïde_), which Antiochus III., in his war with Ptolemy, did not venture to attack on account of its soldiers, its stores, and its population.[423] Moreover, the greater part of the Phœnician towns enjoyed, under the Seleucidæ, a certain autonomy favourable to their industry. In Syria, Seleucia, which Antiochus the Great recovered from the Egyptians, had become the first port in the kingdom on the Mediterranean.[424] Laodicea carried on an active commerce with Alexandria.[425] Masters of the coasts of Cilicia and Pamphylia, the kings of Syria obtained from them great quantities of timber for ship-building, which was floated down the rivers from the mountains.[426] Thus uniting their vessels with those of the Phœnicians, the Seleucidæ launched upon the Mediterranean considerable armies.[427]
Distant commerce also employed numerous merchant vessels; the Mediterranean, like the Euphrates, was furrowed by barques which brought or carried merchandise of every description. Vessels sailing on the Erythræan Sea were in communication, by means of canals, with the shores of the Mediterranean. The great trade of Phœnicia with Spain and the West had ceased, but the navigation of the Euphrates and the Tigris replaced it for the transport of products, whether foreign or fabricated in Syria itself, and sent into Asia Minor, Greece, or Egypt. The empire of the Seleucidæ offered the spectacle of the ancient civilisation and luxury of Nineveh and Babylon, transformed by the genius of Greece.