The war lasted for 50 years 499-449 BCE. The kings were:
Darius I
Xerxes I
Artaxerxes I
Xerxes I.
By the Persian king Xerxes.
For the first phase King Darius I. After his death, it was his successor King Xerxes.
Darius the Great.
Artaxerxes I.
Xerxes I.
Leonidas I, King of Sparta, is the king who died in a battle protecting Sparta from the Persian War.
Exercising his power of king through his generals.
The question is confused. The first king of the Persian empire was Cyrus. The king during the punitive expedition against Athens and Eretria in 490 BCE was Darius. The king during the invasion of Greece 480-479 BCE was Xerxes.
Persian War I, Persian War II, The Peloponnesean War, The Macedonian War, …
On tthe Persian side, the Persian king. On the Greek side, first Sparta, then Athens.
Artaphernes I.