Antigonus emerged from the conflict as the unchallenged ruler of Macedon and the leading power in Greece. After his victory in Argos, Antigonus was able to install his supporter Aristippos as tyrant of Argos and appointed various pro-Macedonian leaders as tyrants in other Greek cities. His support for tyrants over democratic rulers would lead to growing resentment amongst the Greek cities against Macedon. On his journey north to Macedon, Antigonus succeeded in placing garrisons in the cities of Chalcis and Eretria on the important island of Euboia with the outcome being that he further consolidated his power in Greece. The Spartan-Macedon alliance proved to be transient. Angered by Macedon's supremacy and full of ambition, Areus formed a coalition with several Greek poleis, most notably Athens. In the resulting Chremonidean War, Areus was slain by his former ally Antigonus in a battle on the Isthmus of Corinth in 265 BC. The war ended in a defeat that was so crushing for Sparta that it would not rise as a regional power again until the reign of Cleomenes III thirty years later.