At the turn of the year 428, Sitalces raised a massive, multi-ethnic army to march against Macedon and insurgents on the Chalkidiki peninsula. His army consisted of a variety of Thracians (some, like those of the Rhodopes, were independent, but joined nonetheless), Getae and some Paeonians. While Sitalces managed to subjugate some of the Thracian tribes of the lower Styrmon his invasion of eastern Macedon and the Chalkidiki was less successful, as his opponents avoided open combat and simply hid behind their walls. The Odrysian army had not the means to storm them, plus winter was approaching and food supplies were running out. Furthermore, the Athenian force that was promised to them never arrived, perhaps because Athens feared the might of the unleashed Thracian kingdom. After failed negotiations with Perdiccas II Sitalces reteated back home. Thus, after only 30 days the Odrysian invasion had come to an end.