The war between Athens and Macedon erupted in 356, when Phillip moved to strike a series of Athenian ports that had refused goods to the Macedonian Kingdom. Seeing a opportunity to seize the massive gold mines and deposits in the North, Phillip moved his army against the ports, which were relatively undefended. Over the next four years, Macedon successfully defeated the Athenian allies and satellite cities, eventually launching attacks on Athenian colonies, and defeating a series of counter-invasions led by the navy.