Yonā, Yavanā, Yonakā
A country and its people. The name is probably the Pāḷi equivalent for Ionians, the Bactrian Greeks. The Yonā are mentioned with the Kambojā in Rock Edicts V and XII of Asoka, as a subject people, forming a frontier district of his empire. The country was converted by the Thera Mahārakkhita, who was sent there after the Third Council (Mhv.xii.5; Dpv.viii.9; Sp.i.67). In the time of Milinda the capital of the Yona country was Sāgala (Mil.1). It is said (Mhv.xxix.39) that at the Foundation Ceremony of the Mahā Thūpa, thirty thousand monks, under Yona Mahādhammarakkhita, came from Alasandā in the Yona country. Alasandā was evidently the headquarters of the Buddhist monks at that time. Alasandā is generally identified (See, e.g., Geiger, Mhv. Trs. 194, n.3) with the Alexandria founded by the Macedonian king (Alexander) in the country of the Paropanisadae near Kābul.
In the Assalāyana Sutta (M.ii.149), Yona and Kamboja are mentioned as places in which there were only two classes of people, masters and slaves, and the master could become a slave or vice versa. The Commentary (MA.ii.784) explains this by saying that supposing a brahmin goes there and dies, his children might consort with slaves, in which case their children would be slaves. In later times, the name Yavanā or Yonā seems to have included all westerners living in India and especially those of Arabian origin (Cv.Trs.ii.87, n.1). Yonaka statues holding lamps were among the decorations used by the Sākyā of Kapilavatthu (MA.ii.575). The language of the Yavanā is classed with the Milakkhabhāsā (e.g., DA.i.276; VibhA.388).
The Aṅguttaranikāya Commentary (AA.i.51) records that from the time of Kassapa Buddha the Yonaka went about clad in white robes, because of the memory of the religion that was once prevalent there.