the people of Marathon sided with the Persians.
It is historically inaccurate to say that the people of Marathon sided with the Persians. In fact, the people of Marathon were Athenians and they actively fought against the Persians in the famous Battle of Marathon in 490 BCE.
During this battle, the Athenians successfully defended their city against the Persian invasion led by Darius I. They won a significant victory, which was crucial in preserving Greek independence and stopping the Persian advance into Greece.
The Battle of Marathon is considered a defining moment in ancient Greek history and is often cited as an example of Greek unity and resilience against a much larger invading force.