Persia

an ancient empire, extending from the Indus to Thrace, and from
the Caspian Sea to the Red Sea and the Persian Gulf. The
Persians were originally a Medic tribe which settled in Persia,
on the eastern side of the Persian Gulf. They were Aryans, their
language belonging to the eastern division of the Indo-European
group. One of their chiefs, Teispes, conquered Elam in the time
of the decay of the Assyrian Empire, and established himself in
the district of Anzan. His descendants branched off into two
lines, one line ruling in Anzan, while the other remained in
Persia. Cyrus II., king of Anzan, finally united the divided
power, conquered Media, Lydia, and Babylonia, and carried his
arms into the far East. His son, Cambyses, added Egypt to the
empire, which, however, fell to pieces after his death. It was
reconquered and thoroughly organized by Darius, the son of
Hystaspes, whose dominions extended from India to the Danube.