What caused the Greeks to unify in defense of their culture and way of life?

the threat of the Persian Empire conquering Greece
the threat of the Persian Empire conquering Greece

the invasion of Corinth by Thermopylae
the invasion of Corinth by Thermopylae

the attempt of Athens to force democracy on all the poleis
the attempt of Athens to force democracy on all the poleis

the attempt by Sparta to control all of Greece

1 answer

All of the above - the threat of the Persian Empire conquering Greece, the invasion of Corinth by Thermopylae, the attempt of Athens to force democracy on all the poleis, and the attempt by Sparta to control all of Greece - played a significant role in causing the Greeks to unify in defense of their culture and way of life.