Page:The age of Justinian and Theodora (Volume 1).djvu/195

 sons of veterans were impressed into the service, and the landowners had periodically either to provide from their own family or to pay a computed sum for the purchase of a substitute among such as were not liable to conscription. Many of the turbulent barbarian tribes on being subdued were obliged by the articles of a treaty to pay an annual tribute of their choicest youths to the armies of the Empire. In addition to the regular forces, barbarian contingents, called foederati, obeying their own leaders, were often bound by a league to serve under the Imperial government. In Europe the Goths, in Asia the Saracens, were usually the most important of such allies. Of the former nation Constantine at one time attached to himself as many as 40,000, an effort in which he was afterwards emulated by the great Theodosius. The warships of the period were mostly long, low galleys impelled by one bank of oars from twenty to thirty in number, built entirely with a view to swiftness and hence called dromons or "runners." The smaller ones were employed on the rivers, the larger for operations at sea. After a period of service varying from fifteen to twenty-four years the soldier could retire as a veteran with a gratuity, a grant of*