Analysis of information sources in references of the Wikipedia article "ชาวเปอร์เซีย" in Thai language version.
The largest group of people in present-day Iran are Persians (*q.v.) who speak dialects of the language called Fārsi in Persian, since it was primarily the tongue of the people of Fārs."
Conversely, the Nehāvand sub-province of Hamadān is home to ethnic Persians who speak NLori as a mother tongue. (...) The same is true of areas to the southwest, south, and east of the Lori language area (...): while the varieties spoken there show more structural similarity to Lori than to Persian, speakers identify themselves as ethnically Persian.
The name of Fārs is undoubtedly attested in Assyrian sources since the third millennium B.C.E. under the form Parahše. Originally, it was the "land of horses" of the Sumerians (Herzfeld, pp. 181-82, 184-86). The name was adopted by Iranian tribes which established themselves there in the 9th century B.C.E. in the west and southwest of Urmia lake. The Parsua (Pārsa) are mentioned there for the first time in 843 B.C.E., during the reign of Salmanassar III, and then, after they migrated to the southeast (Boehmer, pp. 193-97), the name was transferred, between 690 and 640, to a region previously called Anšan (q.v.) in Elamite sources (Herzfeld, pp. 169-71, 178-79, 186). From that moment the name acquired the connotation of an ethnic region, the land of the Persians, and the Persians soon thereafter founded the vast Achaemenid empire. A never-ending confusion thus set in between a narrow, limited, geographical usage of the term—Persia in the sense of the land where the aforesaid Persian tribes had shaped the core of their power—and a broader, more general usage of the term to designate the much larger area affected by the political and cultural radiance of the Achaemenids. The confusion between the two senses of the word was continuous, fueled by the Greeks who used the name Persai to designate the entire empire.
In 550 B.C. Cyrus (called "the Great" by the Greeks) overthrew the Median empire under Astyages and brought the Persians into domination over the Iranian peoples; he achieved combined rule over all Iran as the first real monarch of the Achaemenid dynasty. Within a few years he founded a multinational empire without precedent—a first world-empire of historical importance, since it embraced all previous civilized states of the ancient Near East. (...) The Persian empire was a multinational state under the leadership of the Persians; among these peoples the Medes, Iranian sister nation of the Persians, held a special position.
By mid-Safavid times the usage tājik for 'Persian(s) of Iran' may be considered a literary affectation, an expression of the traditional rivalry between Men of the Sword and Men of the Pen. Pietro della Valle, writing from Isfahan in 1617, cites only Pārsi and ʿAjami as autonyms for the indigenous Persians, and Tāt and raʿiat 'peasant(ry), subject(s)' as pejorative heteronyms used by the Qezelbāš (Qizilbāš) Torkmān elite. Perhaps by about 1400, reference to actual Tajiks was directed mostly at Persian-speakers in Afghanistan and Central Asia; (...)
