I think your suggestions for Eblana/Eblanoi are ingenious, although the connection with Éblenn and Sliabh Éibhlinne strikes me as more plausible that invoking the Éile. As you indicate, though, there is a geographical mismatch: it's a long way to Tipperary. (Sorry, I couldn't resist that.)
My explanation has the drawback of requiring (a) the variant reading "Ebdanoi" for the people, and (b) the substitution of the "b" by a "p", and then of course (c) the argument that "Ep" represents Gaulish or Brittonic pronunciation corresponding to Irish "Ech". On the other hand, there is the advantage that we know full well that the Ui Echach were a significant group in that locality; and there is the correspondence with the Epidii just across the water in Britain. So I still think I am right about this one!
By the way, would you agree with me that Ptolemy's Gangani is likely to be a syncopation of Galengani?
> Sent: Friday, January 11, 2019 at 2:23 PM
> From: "Paul Tempan" <[log in to unmask]>
> To: [log in to unmask]
> Subject: Re: [OLD-IRISH-L] Ptolemys Tribes of Ireland
> Re-posting my message of 18/04/18 to the Irish Placename Studies forum:
> Ἐβλανα / EBLANA appears an unlocated settlement on Ptolemy's map, but is obviously to be linked with the population group Ἐβλανοι / EBLANOI, whom he places around north Co. Dublin. EBLANA was linked with Dublin by modern antiquarians in the 19th c., which prompted the name to be adopted by the Eblana Theatre in Dublin and a number of Dublin-based businesses. We have an Eblana Street in South Belfast too, which was probably inspired by this supposed link. However, this identification is generally rejected as baseless now.
> I'd like to make a couple of suggestions about these two names. Firstly, I would link EBLANA with the name of the goddess Ébliu, gen. Éblenn, whose name appears in the range of hills Sliabh Éibhlinne in N. Tipperary, misleadingly anglicised as Slieve Felim. The absence of an -n- in the nominative form is not a problem, as the nominative forms in this small declension of words, mostly names, ending in -iu seem to be back-formations, perhaps modelled on Latin nouns ending in -o (ratio, gen. rationis, etc.). The -n- seems regularly to be intrinsic to the earliest forms of these names and is usually only absent in the nominative in Old Irish, but present in all the oblique forms. Thus we have Ptolemy's RIKINA (probably Rathlin), but OIr. Rechriu, gen. Rechrenn; Ptolemy's IOUERNOI, but OIr. Ériu, gen. Érenn. The main objection would probably the location, but the entries in Hogan's Onomasticon Goidelicum for "Eblinn" etc. show that this name was associated not only with Slieve Felim, but also with Cashel in S.E. Tipperary and into Leinster around Cos. Kildare and Carlow., which brings us a good deal nearer to Co. Dublin.
> The second suggestion is that this was originally the same name as Éile, and that the long É- has arisen through fricativisation and eventual loss of the -B-. Éile was a very extensive territiory in the Middle Ages with several sub-divisions, which included Ely O'Carroll and Eliogarty in Co. Tipperary. The name is not only preserved in Durlas Éile (Thurles) and Bearnán Éile (Devilsbit Mountain) in the same county, but also occurs in Brí Éile, an earlier name for the Hill of Croghan in north Co. Offaly, which was regarded as the north-easternmost extent of Éile, again not too far away from Co. Dublin. This leaves us with only a slight geographical difference between Ptolemy's placing of the EBLANOI and the later medieval location of Éile and names connected with Ébliu. This could be due either to inaccuracy on Ptolemy's part or movement and expansion in the intervening centuries. EBLANA as a town is unlocated, but if I had to guess I would put my money on a settlement near the Hill of Croghan, its early importance being shown by the discovery of Croghan Man, who is likely to have been an executed king.
> I welcome any thoughts and alternative ideas.
> All the best,