On the Italian mainland the Syracusan ascendancy melted away on the death of Dionysius. The great tyrant had made use of the Lucanians and other Italians to bring the Greek colonies under his sway. When he died the Italians combined and formed the Bruttian League against the divided Greeks, pressing them so hard that Tarentum appealed for aid against the barbarian to its mother city Sparta (343 BC).
Sparta responded and King Archidamus headed an expedition. The expedition failed disastrously and the king was killed in battle with the Lucanians in 338 BC.
Greece could not immediately react, but in 334 BC, when Alexander the Great was starting on the great eastern venture, his uncle Alexander 'the Mossian' of Epirus answered to call of the western Greeks, perhaps with imperial dreams of his own. His success was rapid, but in 330 BC his career was cut short by the dagger of an assassin before he could consolidate his power in Italy.
When he fell he had already formed an alliance with the advancing Roman state whose foes in the south were also his enemies. But he left no successor to carry on his projects.