Darius recrossed the river after an interval of somewhat more than two months, victorious according to his own notions, and regarded himself as entitled thenceforth to enumerate among the subject races of his empire "the Scyths beyond the sea." On his return march through Thrace, he met, apparently, with no opposition.

Before passing the Bosphorus, he gave a commission to one of his generals, a certain Megabazus, to complete the reduction of Thrace, and assigned him for the purpose a body of 80,000 men, who remained in Europe while Darius and the rest of his army crossed into Asia.
Megabazus appears to have been fully worthy of the trust reposed in him.
In a single campaign (B.C.

506) he overran and subjugated the entire tract between the Propontis and the Strymon, thus pushing forward the Persian dominion to the borders of Macedonia.

Among the tribes which he conquered were the Perinthians, Greeks; the Pseti, Cicones, Bistones, Sapaei, Dersaei and Edoni, Thracians; and the Paeoplae and Siripasones, Pseonians.

These last, to gratify a whim of Darius, were transported into Asia.