The Greeks fought the Persians in the Greco-Persian Wars
King Philip did not conquer Persia because he was assassinated.
Xerxes was king of Persia and battled against Sparta and Athens. etc
Amestris or Amastris was the wife of King of Kings Xerxes I of Persia, mother of king Artaxerxes I of Persia.
Persia
The king ruled Persia because the greatest god allowed him to.
The phrase "he loyal fights for his king" is grammatically incorrect. It seems to be a mix of two ideas: "He fights for his king" (transitive) and "He is loyal" (intransitive). If you want to combine them, you can say "He is loyal and fights for his king" to maintain clarity.
Xerxes was the king of ancient Persia.
Xerxes when he is referenced by the Greeks. In the Bible his name begins with an A.
King Cyrus the Great.
most of them died but the king bought more
Cyrus, King of Persia.
Cyrus, Darius, Xerxes.