Examples of Old Persian have been found in what is now Iran, Romania (Gherla),[3][4][5] Armenia, Bahrain, Iraq, Turkey and Egypt,[6][7] with the most important attestation by far being the contents of the Behistun Inscription (dated to 522 BCE).
According to certain historical assumptions about the early history and origin of ancient Persians in Southwestern Iran (where Achaemenids hailed from), Old Persian was originally spoken by a tribe called Parsuwash, who arrived in the Iranian Plateau early in the 1st millennium BCE and finally migrated down into the area of present-day Fārs province.
[10] Assyrian records, which in fact appear to provide the earliest evidence for ancient Iranian (Persian and Median) presence on the Iranian Plateau, give a good chronology but only an approximate geographical indication of what seem to be ancient Persians.
[12] The group of Old Iranian languages was presumably large; however, knowledge of it is restricted mainly to Old Persian, Avestan, and Median.
The first two are the only languages in that group to have left written original texts, while Median is known mostly from loanwords in Old Persian.
[16][17] Comparison of the evolution at each stage of the language shows great simplification in grammar and syntax.
Median forms "are found only in personal or geographical names [...] and some are typically from religious vocabulary and so could in principle also be influenced by Avestan."
[20] The origin of the Old Persian cuneiform script and the identification of the date and process of introduction are a matter of debate among Iranian scholars with no general agreement having been reached.
The factors making the consensus difficult are, among others, the difficult passage DB (IV lines 88–92) from Darius the Great who speaks of a new "form of writing" being made by himself which is said to be "in Aryan": King Darius says: By the grace of Ahuramazda this is the inscription which I have made.
Besides, a sculptured figure of myself I made.Also, the analysis of certain Old Persian inscriptions are "supposed or claimed" to predate Darius the Great.
Although it is true that the oldest attested Old Persian inscriptions are found on the Behistun monument from Darius, the creation of this "new type of writing" seems, according to Schmitt, "to have begun already under Cyrus the Great".
Lycian 𐊋𐊆𐊈𐊈𐊀𐊓𐊕𐊑𐊏𐊀 Kizzaprñna ~ 𐊈𐊆𐊖𐊀𐊓𐊕𐊑𐊏𐊀 Zisaprñna for (genuine) Old Persian *Ciçafarnā (besides the Median form *Ciθrafarnah) = Tissaphernes suggests /t͡s/ as the pronunciation of ç (compare [1] and Kloekhorst 2008, p. 125 in [2] for this example, who, however, mistakenly writes Çiçafarnā, which contradicts the etymology [PIIr.
For example, Old Persian Vᵃ-rᵃ-kᵃ-a-nᵃ /wr̩kaːna/ is rendered in Elamite as Mirkānu-,[23] rendering transcriptions such as V(a)rakāna, Varkāna or even Vurkāna questionable and making Vrkāna or Virkāna much more realistic (and equally for vrka- "wolf", Brdiya and other Old Persian words and names with syllabic /r/).