Ariana was a general geographical term used by some Greek and Roman authors of the ancient period for a district of wide extent between Central Asia and the Indus River, comprising the eastern provinces of the Achaemenid Empire that covered the whole of modern-day Afghanistan, as well as the easternmost part of Iran and up to the Indus River in Pakistan. Ariana is the Latinized form of the Ancient Greek Ἀρ(ε)ιανή (inhabitants: Ariani; Ἀρ(ε)ιανοί ), originating from the Old Persian word (Ariana) meaning 'the Land of the Aryans', similar to the use of Āryāvarta.
At various times, various parts of the region were governed by the Persians (the Achaemenids from 550 to 330 BC, the Sasanians from 275 to 650 AD and the Kushano-Sasanians from 345 to 450 AD), the Macedonians, the Seleucids from 330 to 305 BC, the Maurya Empire from 305 BC to 184 BC, then the Greco-Bactrians from and the Indo-Greeks from 155 to 90 BC, the Indo-Scythians from 90 BC to 20 AD, the Parthians from 160 BC to 225 AD including the Indo-Parthians from 20 to 225 AD and the Kushans from 110 BC to 225 AD, the Xionites (the Kidarites from 360 to 465 AD and the Hephthalites from 450 to 565 AD) and various other Huna peoples.
The Greek term Arianē (Latin: Ariana), a term found in Iranian Avestan (especially in Airyanem Vaejah, the name of the Iranian peoples' mother country). The modern name Iran represents a different form of the ancient name Ariana, which was derived from Airyanem Vaejah and implies that Iran is the Ariana itself, a word that is found in Old Persian, a view supported by the traditions of the country preserved in the Muslim writers in the 9th and the 10th centuries.
The Greeks also referred to Haroyum/Haraiva (Herat) as Aria, which is one of the many provinces found in Ariana.
The names Ariana and Aria and many other ancient titles, of which Aria is a component element, are connected with the Avestan term Airya-, and the Old Persian term , a self-designation of the peoples of Ancient Iran and Ancient India, meaning 'noble', 'excellent' and 'honourable'.