Ask most people about the origins of the marathon—a race covering 26.2 miles of terrain—and you will likely hear about how Pheidippides, an ancient Greek courier, ran 26 miles from the town of Marathon to Athens to announce the Greek victory in a decisive battle over the Persians—then died on the spot. As legend would have it, the Greeks honored the herald by adding a “marathon” to the ancient Olympic Games.

But the true history is more complex and convoluted­. Here’s how the race got its name—and why everything you’ve ever heard about the sport may be wrong.

First, the facts: There was an ancient Greek named Pheidippides, and he did work as a courier during the war against the Persians in