WBEZ brings you fact-based news and information. Sign up for our newsletters to stay up to date on the stories that matter.In 490 B.C., an infantry of over 20,000 Persian forces invaded Marathon, Greece, sparking the Battle of Marathon. Known as one of the earliest recorded battles in history, the invasion had less to do with running than it did with military strategy. Historian John R. Schmidt tells us about the significance of this event. (Photo: Wikimedia Commons).