List the most important reasons that allowed the Greeks to defeat the Persians in the 5th century BC

List the most important reasons that allowed the Greeks to defeat the Persians in the 5th century BC, and the Macedonians to conquer the Greeks.

The main reasons for the victory of the Greeks:

They fought for their land and freedom;
The Greeks were united, and the Persians led the armies of different nations;
The Greeks were commanded by skillful generals (Miltiades, Themistocles, etc.).

The main reasons for the victory of the Macedonians over the Greeks:

The Greek city-states were disunited;
Tsar Philip 2 skillfully used the strife between the Greek city-states and wove political intrigues (bribery and persuasion);
The Macedonian army was quite strong.