The Battle of Marathon was fought because the Persian Army wanted to defeat the Greek city-states that supported the uprisings in Ionia, part of modern-day Turkey, against the Persian Empire.

The first encounter on the Greek mainland between East (Persia) and West (Greece) took place in August or September of 490 B.C., on the small seaside plain of Marathon, 26 miles northeast of Athens. The Persian expeditionary force of Darius I was not large, perhaps numbering under 30,000.

Led by generals Hippias, Datis and Artaphernes, the Persian Army arrived confident after storming the nearby Greek city-state of Eretria. No allies except the Plataeans joined the Athenian resistance of less than 10,000 troops, and some autocratic regimes in Attica supported the invaders in the hope of toppling the fledgling democracy.

To meet the larger invading force, the Athenian army commander Miltiades thinned out his army's center and reinforced the wings, hoping that his hoplites—heavily armed foot soldiers—could hold the middle while his flanks broke through the lighter-clad Persian infantry. In fact, the Athenian center broke, but it held long enough for the Athenians to rout the Persian wings and meet in the rear, causing a general panic among the invaders.

The Persians would invade Greece again in 480 B.C. under Xerxes I, son of Darius, who planned to succeed in conquering Greece where his father had failed. The allied Greek city-states under King Leonidas of Sparta held off the Persian invasion for seven days in the Battle of Thermopylae, earning them a place in history for their last stand in defense of their native soil. But it was the initial victory of the Athenians at the Battle of Marathon that is most remembered today.

Almost immediately, the victory of “the Marathon men” captured the collective imagination of the Greeks. Ceremonial funeral mounds of the legendary 192 Athenian dead and the loyal Plataeans were erected on the battlefield. Epigrams were composed and panoramic murals were put on display.

Most of what we know about the Battle of Marathon comes from the account of the historian Herodotus, who wrote about it around 50 years after the battle took place in his Histories. Another famous author to immortalize the Battle was Robert Browning, who wrote the poem “Pheidippides” in 1879 to commemorate the soldier’s run from Marathon to Athens.

The first organized marathon was part of the first modern Olympics in 1896. The ancient games, held from approximately 776 B.C. to 393 A.D., did not include the race.

Michael Bréal, a friend of modern Olympics founder Pierre de Coubertin, was inspired by the legend of the Battle of Marathon to create an endurance race. The first marathon was 40 kilometers, or under 25 miles (as opposed to today’s 26.2 miles), and almost half of the competitors had to quit from exhaustion. The winner of the first marathon was Spiridon Louis, a Greek shepherd who never ran another competitive race again.

The journey of Pheidippides from Marathon to Athens also inspired the first Boston Marathon on April 19, 1897. The Boston Marathon is the world’s oldest annual marathon and is also notable for allowing women to compete in 1972 when the first Olympic marathon for women wasn’t held until 1984.