The Battle of Marathon, Greek Μάχη τοῡ Μαραθῶνος (Machê tou Marathônos), took place in 490 BC an was the culmination of King Darius I of Persia's first full scale attempt to conquer the remainder of Greece and incorporate it into the Persian Empire, which would secure the weakest portion of his western border. Most of what is known of this battle comes from the Greek historian Herodotus. In Persian sources, there is no mention of such a battle.