It has been a good while since the concept of the five double-u(s) has crossed the horizon of my mind. This concept has been used multiple times in the tree climbing experience for my own ancestors. Considering my Celtic group of folks it would go something like this: 1) who = Celtic, 2) what = migration to NW Wales, 3) when = 500 - 400 B.C., 4) where = Vale of Clwyd and Vale of Dee, 5) why = is where I have come for this post.
The why has often been the toughest to figure out among the branches. Why would my Celtic ancestors want to make such a trip? It would be hard enough to get here, hard enough to land, and hard enough to survive while keeping the family going. Life and/or limb, or any other vital parts of the body, would probably be first on my list of whys. Life and/or limb of wife and children would be second. Brother, sister, father, mother, aunts, uncles, cousins, etc. would come somewhere in the list of why. Family is thicker than blood they would often say in my present family that have resided more than 200 years in the Bluegrass of Kentucky. Guess this thought has been passed down through the ages.
In addition, the why for this geographic area of the world for my Celtic ancestors must have had something to do with salt. The earliest folks had their beginning in salt mines around Hallstatt, Austria. Salt mining and salt trading were key to the stabilization of the Celtic culture. As a fact, this element became the very word for the "Hallstatt Period". The realization that salt would help the meat last longer must have been an added benefit.
Now one had to keep the salt in some kind of container which could be carried and stored safely. This became known as the "briquetage container" [p.688, Green et. al], and helped define another developmental period for these Celts as La Tene. [need a special accent "the grave" over first e]
Finally was the element iron. The Celts became experts in the use of iron. All kinds of weapons, tools, art work, wearing apparel, etc., to name a few. Must have traded their salt for a bit of this metal. By the time my ancestors traveled to their landing spot in NW Wales, salt and iron would have been on their list of needs. Now the mouth of the Dee was one of the best places to manufacture salt on this island. [Cheshire salt p.688, Green et al] and the Vale of the Clwyd and would have iron. What a deal, two for one at the family settlement.