Ionic uprising is the name usually given to the initial phase preceding the Persian Wars.
In the course of the second half of the 6th century BC. it came to an ever-increasing polarization between the expanding Persian empire and the Greek colonial expansion in the Black Sea and in the eastern part of the Mediterranean. When Athens refused to re-adopt the Athenian tyrant Hippias to Persia, it was perceived by Persia as a declaration of war by all Greeks. Especially the Greek coastal cities of Ionia (the west coast of Asia Minor) suffered worse Persian pressure: the conquest of Egypt and Hellespont became a serious obstacle to their overseas trade. To defend their common interests, different cities joined a state union, the so-called Panionion. In particular, Milete offered great resistance to the Persians, who wanted to annex the prosperous trading city. Despite the diplomatic activity of the Milesian tyrant Histiaeus broke out in 499 in this area a revolt against Persian authority.
Sparta refused all help, but Athens and Eretria (as well as some other city states) sent a fleet. These troops destroyed the city of Sardes, the Persian power center in Asia Minor, but the rebellion was dropped by Darius I: it lacked the unity of the Greeks and a powerful leadership which the king used. In 494 the Greek expedition fleet for the Ionian coast was smashed in the Battle of Lade. The following year Milette was conquered and destroyed completely. King Darius then prepared for a criminal expedition against the Athenians and the Eretrians because of their support for the Ionian uprising. This would end on the first Persian War.
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