How did the Persian-Greek war start?

Answer 1

King Croesus of Lydia died, and the Ionian Greeks came under the domination of the Persian Empire which they much resented, so they fought to throw out the Persians in the Ionian Revolt. Athens and Eritrea supported the Ionians with a token force (20 ships from Athens, 5 ships from Eritrea). The Ionian Revolt was successful at first, but after the Greeks sailed home it was crushed. Persian temples had been violated, and whether they did it or not the Athenians and Eritreans were blamed for it. King Darius I of Persia ordered a punitive expedition to these two cities, but a storm smashed his fleet. Another fleet was assembled, and the First Persian War began in 490 BC. Athens was saved at the Battle of Marathon, but Eritrea was destroyed.

Answer 2

The Greek city-states in Asia Minor revolted against Persian rule in 499 BCE, resulting in a 50 year war.