By the time Cleomenes III became king in 235 BC, Spartan power and prestige had been in steady decline for a century and a half. The state that had defied the Persians at Thermopylae and Plataea and humbled the Athenians in the Peloponnesian War was reduced to a minor player in Greek affairs. Sparta had never recovered from defeat by the Thebans at Leuktra in 371 BC. Much of its territory had been lost and its army, once feared and respected throughout the Eastern Mediterranean, was outdated and crippled by a chronic manpower shortage. Cleomenes sought to change all that and this book assesses his attempts to make Sparta into a force to be reckoned with once more. He combined revolutionary social reforms (egalitarian redistribution of land, thus enfranchising far greater numbers of men but also making them eligible for military service), with a revival of traditional Spartan discipline and martial values (reinstating the agoge system by which Spartan males trained as soldiers from the age of 7). Furthermore, a series of long-overdue military reforms saw the traditional hoplite phalanx surrendered in favor of Macedonian models. The revival of Sparta's martial vigor and territorial ambitions did not go unnoticed by her neighbors of course, leading to five years of warfare with the Achaean League and Macedon, culminating in the tactically fascinating Battle of Sellasia (222 BC) which effectively ended Spartan power forever.