16
HISTORY
challenging the Eastern Empire by dominating the Adriatic. In 812, however, chiefly owing to the defeat of his son Pepin before Venice, he abandoned his attempt and came to terms with the Emperor Nicephorus. The coast towns of Dalmatia remained subject to Byzantium, though the Croat Zupans continued to rule on the mainland. Constantine, writing his Treatise on the administration of the Empire, says: “ The Croats, like the rest of the Slav peoples, have no other rulers
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than their Zupans ; and they governed all Dalmatia, except the cities on the sea-coast, which continued to live under Rome and drew their sustenance from the sea”. The Roman Byzantine influence led to the Christianization of a large part of Dalmatia; but the Paganoi, as they were called, round the mouth of the Narenta remained unbaptized heathens.
  With the appearance of Venice, however, on the scene a new era in Dalmatian history was about to open. The young Republic, rapidly expanding under the stimulus of its victory over and preservation from Charlemagne and the Franks, soon found that the development of its commerce depended on naval supremacy in the northern Adriatic, and that that again depended on the suppression of the Liburnian and Illyrian pirates who sheltered in the channels,