Persis

Persis Περσίς
Region
The ruins of Persepolis

Persis (Greek: ), better known as Persia (Old Persian: Parsa; Persian: پارس‎‎, Pars), or "Persia proper", was originally a name of a region near the Zagros mountains at Lake Urmia. The country name Persia was derived directly from the Old Persian Parsa. Over time, the area of settlement shifted to the southwest of today Iran (now Fars).

The ancient Persians were present in the region from about the 10th century BC, and became the rulers of the largest empire the world had yet seen under the Achaemenid dynasty which was established in the late 6th century BC, at its peak stretching from Thrace-Macedonia, Bulgaria-Paeonia and Eastern Europe proper in the west, to the Indus Valley in its far east. The ruins of Persepolis and Pasargadae, two of the four capitals of the Achaemenid Empire, are located in Fars.

The Achaemenid Empire was defeated by Alexander the Great in 333 BC, incorporating most of their vast empire. Shortly after this the Seleucid Empire was established. However it never extended its power beyond the main trade routes in Fars, and by the reign of Antiochus I or possibly later Persis emerged as an independent state that minted its own coins.

The Seleucid Empire was subsequently defeated by the Parthians in 238 BC. By 205 BC, Antiochus III had extended his authority into Persis and it ceased to be an independent state.

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Wikipedia