Is it the Persian War or the Persian Wars

Persian War or Wars it doesn’t matter much – it was ongoing from the Persian put-down of the Ionian Revolt from 499 BCE, through their invasion of mainland Greece in 480 BCE until a formal peace in 449 BCE.

There were also fights involving the Persians and various Greek city-states, from the takeover of the Asian-Greek cities in the late sixth century BCE through to the 4th Century BCE.

The actual war/wars had several phases:

The Ionian Revolt 499-493 BCE.
The Persian punitive expedition against Eretria and Athens 490 BCE.
The Persian invasion of peninsular Greece 480-479 BCE.
The Greek city-states counter-offensive 478-449 BCE.

Some people ill-informedly talk of First Persian War, Second Persian War, Third Persian War; others talk of First and Second Persian Wars. It is difficult to reconcile these classifications with the above phases, and it is better avoid them as it is simply confusing as well as innacurate.