after her eventual defeat by sparta in 404 bc, athens soon recovered and re-established her hegemony over euboea, which was an essential source of grain for the urban population. the eretrians rebelled again in 349 bc and this time the athenians could not recover control. in 343 bc supporters of philip ii of macedon gained control of the city, but the athenians under demosthenes recaptured it in 341 bc.