In Indo-European Poetry and Myths page 142, M.L. West points out that the both the name Iran (Airan) and Irish Eire coming from Aire “a noble lord,” developed from the same root as the Zoroastrian Airyaman or literally “Aryan-ness,” the divine principal of “honor, goodness, virtue, and nobility.”
West mentions other cognates with the Zoroastrian Airyaman in other Indo-European languages including the other name/title of Odin Iormunr, the Irish Eremon, and the Old English Eormencyn “noble, mighty race.”
The poetic gathas of prophet Zarathustra start with the “will to become godlike” ahü vairyö and concludes with airyemá išyö “the noble lordship or higher ideal.”
The xᵛarənah or farnah “fiery splendor/fortune” that created the worlds in the Avesta, is coupled with airyanąm xᵛarənö “fiery glory of the Aryans,” and the luminous vision daæná of the Zoroastrian religion that will again make the creations frašö “splendid, new, excellent” in an eternal spring.
In the Avestan lore Airya is an ethnic epithet and contrasts with other ethnic groups such as Tüirya, Sairima, Dāha, Sāinu, and with the outer world of the An–Airya “non-Aryans.”
Old Persian ariya– occurs in the phrase of Darius the Great: ariya: ariya: ciça, “Arya, of Aryan origin,” and of Xerxes: pārsa:pārsahyā: puça: ariya: ariyaciça, “a Persian, son of a Persian, Arya, of Aryan origin.”
The phrase with ciça, “descent, ancestry, and roots” assures that the term arya is an ethnic designation wider in meaning than parsá, and not a simple adjectival epithet.
The ancient native Elamites have preserved the gloss to the name of the supreme god Ahûrá Mazdá in DB 4.89 Behistun 62: u-ra-mas-da na-ap har-ri-ia-na-um, “Ahûrá Mazdá, god of the Aryans.
Kava Hû-sravö of “good glory” is called arša airyanąm “the bull/champion (aršan– “male”) of the Aryas, in Yašt. 15.32, of the Avesta.
The all noble/Aryan forest called vīspe.aire.razuraya (Yt. 15.32) was where Hû-sravö of “good repute” slew the evil, lower wind.
Avestan ereḵšö or araḵš “bear man” is the archer of the Aryans in the Avesta. The Tri-star hymn states that like the mind-swift arrow which the archer ereḵšö shot, swift-arrowed, most swift-arrowed of the Aryas, from Mount Airyö-xšuθa to Mount Xvanvant.” yaθa tiγriš mainya-asǡ yim aŋhaṱ ərəxšō xšviwi.išuš xšviwi.išvatəmō airyanąm airyō.xsuθaṱ hača garōiṱ xᵛ anvantəm avi gairīm
The airyanąm dahyunąm “lands of the Aryans” in the Avesta contrasts with anairya– “non-Arya lands” anairyǡ diŋhāvō. This dichotomy is continued later in Persian Zoroastrian tradition. Airyö.šayana– “dwelling of the Aryans” is also another recurring term in the Avesta.
airyanəm vaēǰō “cradle of the Aryans” is the first/most pristine of all the beautiful lands created by Ahûrá Mazdá (Vidēvdāt 1.3) and is the birth place of Prophet Zarathustra, the term is frequented in Zoroastrian apocalyptic literature, and in connection with the coming eternal spring.
The holy Denkart, the great encyclopedia of Zoroastrianism associates arya– “honorable, Aryan” with good, healthy lineage/birth among mortals” hû-töhmaktom ēr martöm. This phrase in holy Denkart compares with ariya-čiça in the Old Persian Inscriptions.
Similarly ērīh ut dahyupatīh “honor and lordship,” contrasts with arg ut bār hač škōhišn, “labor and burdens from poverty” in holy Denkart.
I shall conclude by stating that both Ireland and Iran refer to the “land of the Noble Ones” and harken back to the ancient Indo European forgotten past. To an age when the land was sacred, and a mighty noble people endeavored to re-create Asgard here on earth through “goodness, honor and virtue.”