Good morning. Interesting reading there David.
The Dagda – Dagodeiwos – has many names, including Ollathair (All Father) and Fer Benn (Horned/Peaked One) as well as Dáire (Fertile One). He also has the coire ansic (cauldrdon) and a staff, lorg mór or anfaid and an oak harp, the Daur da Bláo (Oak of Two Flowers). The Dagda is very much a chthonic, earth and fertility deity it seems. With the name Ollathair, it would be tempting to see a similarity with Odin/Woden, who in Norse tradition is called Foldardróttinn (Lord of the Earth) and, notably, Alföðr (All Father). Turning to British tradition, the name Gwydion could also be linked in different ways, etymologically, to Woden and given the shapeshifting, trickster-like, nature-based characteristics and epithets along with the connection to trees that all of these figures share in one way or another, it is at least food for thought. Having said that, I’d be careful about jumping to too many conclusions either.