Who is the Persian king who invaded Greece in 490?

The Persian king who invaded Greece in 490 BCE was Darius I, also known as Darius the Great. He sought to expand his empire and punish the Greek city-states that had supported a revolt in Asia Minor. This invasion culminated in the famous Battle of Marathon, where the Athenians achieved a significant victory against the Persian forces. Darius's campaign ultimately laid the groundwork for further conflicts between Persia and Greece.