History of the Peloponnesian War

For they established their custom the very reverse of that in the Persian kingdom, (though it prevails amongst the rest of the Thracians also,) namely, to receive rather than to give; and it was considered more disgraceful not to give when asked, than not to succeed by asking. But [though the other Thracians practised the same thing], still the Odrysians, owing to their greater power, practised it to a greater extent; for it was impossible to get any thing done without making presents.

The kingdom then had reached a high pitch of power. For of all those in Europe between the Ionian Gulf and the Euxine Sea, it was the greatest in amount of revenue and general prosperity; while in military power and number of troops it was decidedly next to that of the Scythians.

But with this not only is it impossible for those in Europe to vie, but even in Asia, putting one nation against another, there is none that can stand up against the Thracians, if they are all unanimous. Not, however, that they are on a level with other men in general good management and understanding in the things of common life.

Sitalces, then, being king over all this extent of country, prepared his army to take the field. And when all was ready for him, he set out and marched against Macedonia; at first through his own dominions, then over Cercine, a desert mountain, which forms the boundary between the Sintians and Paeonians, crossing it by a road which he had himself before made, by felling the timber, when he turned his arms against the Paeonians.

In crossing this mountain from the Odrysians, they had the Paeonians on their right, and on their left the Sintians and Maedians; and after crossing it they arrived at Doberus in Paeonia.

While he was on the march, there was no diminution of his army, (except by disease,) but accessions to it; for many of the independent Thracians, though uninvited, followed him for plunder; so that the whole number is said to have been not less than one hundred and fifty thousand, of which the greater part was infantry, but about a third cavalry.