At the beginning of the 5th century BC Alexander I benefited from both the attempted expansion of the Persians in Europe and their defeat in the Persian Wars: he more than doubled his dominions, extending the borders of his kingdom from the Axios to the Strymon rivers, and imposing his authority on the kings of Upper (present-day Western) Macedonia. He also contributed to the economic and social modernization of Macedonia, minting coinage and attracting to his court renowned intellectuals as well as thousands of ordinary citizens from southern Greece.
The expansionist tendencies of Athens and the subsequent Peloponnesian War frequently caused embarrassment to his heir Perdikkas II (454-413 BC). Perdikkas' son Archelaos (413-399 BC), in contrast, made the most of the Athenians' weakness and continued his grandfather's reforms. Archelaos' death was followed by a period of dynastic crises, barbarian incursions and foreign intervention, surmounted with difficulty by his successors Amyntas III (394-370 BC) and Perdikkas III (365-360 BC). The defeat and death on the battlefield of the latter, and the accession to the throne of his younger brother Philip II marked the beginning of Macedonia's recovery.