<P> The Spartan hegemony lasted another 16 years, until, when attempting to impose their will on the Thebans, the Spartans were defeated at Leuctra in 371 BC . The Theban general Epaminondas then led Theban troops into the Peloponnese, whereupon other city - states defected from the Spartan cause . The Thebans were thus able to march into Messenia and free the population . </P> <P> Deprived of land and its serfs, Sparta declined to a second - rank power . The Theban hegemony thus established was short - lived; at the Battle of Mantinea in 362 BC, Thebes lost its key leader, Epaminondas, and much of its manpower, even though they were victorious in battle . In fact such were the losses to all the great city - states at Mantinea that none could establish dominance in the aftermath . </P> <P> The weakened state of the heartland of Greece coincided with the Rise of Macedon, led by Philip II . In twenty years, Philip had unified his kingdom, expanded it north and west at the expense of Illyrian tribes, and then conquered Thessaly and Thrace . His success stemmed from his innovative reforms to the Macedonian army . Phillip intervened repeatedly in the affairs of the southern city - states, culminating in his invasion of 338 BC . </P> <P> Decisively defeating an allied army of Thebes and Athens at the Battle of Chaeronea (338 BC), he became de facto hegemon of all of Greece, except Sparta . He compelled the majority of the city - states to join the League of Corinth, allying them to him, and preventing them from warring with each other . Philip then entered into war against the Achaemenid Empire but was assassinated by Pausanias of Orestis early on in the conflict . </P>

Who developed the first civilization in the greek world