Peria is an ancient empire that extended from the Indus River 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.
Now in the first year of Cyrus king of Persia, that the word of the LORD spoken by the mouth of Jeremiah might be accomplished, the LORD stirred up the spirit of Cyrus king of Persia, that he made a proclamation throughout all his kingdom, and put it also in writing, saying,
Thus saith Cyrus king of Persia, all the kingdoms of the earth hath the LORD God of heaven given me; and he hath charged me to build him a house in Jerusalem, which is in Judah.” —2 Chronicles 36:22-23
Artaxerxes and his sons Sogdianus and Darius II Nothius
World’s largest empire
With close to 50-million people, the ancient Persian empire, under the rule of Darius I, was the world’s largest by percentage of world population, according to the Guinness Book of World Records:
By share of population, the largest empire was the Achaemenid Empire, better known as the Persian Empire, which accounted for approximately 49.4 million of the world’s 112.4 million people in around 480 BC—an astonishing 44%.
Politically, Persia, in modern times, came to be known as Iran, with its 5 largest cities being Tehran, Mashhad, Isfahan, Karaj and Shiraz. Culturally, the names “Persia” and “Iran” are today used interchangeably. The Persian-language, “also known as Farsi, is the most widely spoken member of the Iranian branch of the Indo-Iranian languages.”