There was no city of Marathon. It was a plain 26 miles north of Athens.
Not a city - the Plain of Marathon.
Athens. Marathon was a plain, not a tiny seaport town.
It was not the Greeks but the Greek city-state of Eretria.The Persians then switched to Athens which defeated them at Marathon.
Marathon was a plain. The combined armies of Athens and Plataea defeated a Persian punitive expedition on the Marathon plain.
Not the Greeks, but the Greek city-states of Athens and Plataea, The battle in 490 BCE was on the plain of Marathon (not a city) 26 miles north of Athens.
Marathon was a plain. Athens and its ally Plataea defeated a Persian punitive expedition on the plain.
Control of the Greek city-states in Asia Minor - however they took them back 50 years later as the Greeks fought each other.
It was the other way round - the Athenians and Eretrians burnt the Persian provincial capital of Sardis in 498 BCE, which caused the Persians to try to suppress them, frustrated by their loss at Marathon.
Marathon was a plain, not a city. It was owned by Athens. They fought a battle against a Persian amphibious punitive expedition sent by Persia in 490 BCE.
Plataea.
There were nearly 200 city-states who united to fight off the Persians.
The Persian Empire versus varying combinations of Greek city-states.