Another considerable element of the ancient population was the Iverni, as they were called by Ptolemy in the second century. Ptolemy locates them in the middle of southern Ireland. The Irish form of their name in the time of our most ancient writings was Érainn, more familiar in later usage in the accusative form Érna. They have been sometimes called Erneans in English. In the older heroic literature, the Iverni or Érainn are the chief people of Munster. In an important early tract, which gives the names and distribution of the principal subject communities throughout Ireland, the Sen-Érainn are placed in the district of Luachair, i.e., in the north of Kerry and the adjoining parts of the counties of Limerick and Cork. The peoples enumerated in this tract are regarded as being not of Gaelic origin. Sen-Érainn means the old or original Iverni, and the term is used to distinguish them from others also called Érainn, who were of free status and are attached by the genealogists to the Gaelic stock. My opinion is that the dominant element in every part of Ireland during the historical period, including the dynastic families and higher nobility, was Celtic. Otherwise, if we suppose that large communities of pre-Celtic inhabitants continued to exist under rulers and nobles of their own stock down to medieval times, the universality of the Gaelic language as far back as tradition reaches would be hard to account for. I suppose that, when a Celtic dynasty and nobility became established over a non-Celtic commonalty, the old name of the community became attached to them all. So we find that Giraldus calls the nobles who invaded Ireland in his time Angli, giving them the name of the subject people over whom they had ruled in England, though they had been barely a century in England and some of them not nearly so long. I think the same is probably true of the free and dominant Picts in the north-east, i.e., that they consisted of a common population of Pictish stock ruled by kings and nobles of Celtic origin.

Not only in Munster but also in Connacht, Meath and Ulster, our ancient genealogists recognise the existence of Ivernian communities. Rhys put forward the view that the Iverni were only a southern division of the Picts, but this view cannot well be reconciled with Irish tradition, which seems always to distinguish between Picts and Iverni, and recognises Picts in southern Ireland and Iverni in northern Ireland. For example, in county Antrim, Dál Riada, the north-eastern portion, was Ivernian, and the rest of the county for the most part was Pictish. We are on safer ground in regarding the Picts and the Iverni as two fairly distinct peoples.

From the Iverni the whole island took the names by which it was known to the ancient Irish, the Britons, the Greeks, the Romans, and therefore no doubt to the Celts in the neighbouring parts of the Continent. But we have seen that the original Iverni, in Irish tradition, were a remnant of the pre-Celtic population. Ireland therefore was named by the Celts, as Britain and Ireland were jointly named, from an older population which the invading Celts found in possession. The Romans changed Iverni into Hiberni, through a process known as popular etymology. Hiberni suggested to them the Latin word meaning "wintry." Though Ireland was known to some Latin writers to be by no means a wintry country, but quite the contrary, this verbal resemblance naturally caught the imagination, and one Latin poet actually speaks of "glacialis Ierne," ice-cold Ireland.

The Irish and Welsh names of Ireland are not directly taken from the name of the Iverni, but evidently from an older form which must have been Ivéri. Both the Irish name Éire (formerly Ériu) and the Welsh Iwerddon go back to an older name Iverio, and this older name is actually found in the writings of Saint Patrick in the slightly disguised Latin form Hiberio. The Irish genealogies corroborate this view that the name Iverni is itself a derivative from an older name Iveri. A common feature in genealogical lore is the tracing of a people's descent from an ancestor of the same name. It is found in the Bible, in the genealogies of the Arabs, in the legends of the Greeks, and in our own legends, for example, when the Gaels are said to have taken their name from an ancestor named Gaedheal Glas. In like manner all the pedigrees of the Érainn or Iverni in the Irish genealogies are traced to an ancestor named Iar. Iar is a word of two syllables, and represents an older form Iveros. From this and from the Irish and Welsh names of Ireland, I infer that the people called Iverni were at a still earlier period called Iveri. The change in the name of a people from a simple to a derivative form is of very common occurrence. Thus, instead of Angles, people now say the English, instead of Scots, the Scotch; in Irish, the names for the English and the Welsh have undergone a similar change; and so with numerous other names in many countries and languages.

Rhys derives the old Celtic name of Ireland, Iverio, from a word cognate with the Greek piaira, meaning "fat," and understands Iverio to mean the fat, i.e., the fertile country. This explanation, however, will not hold good if, as I think, the name Iverio means the country of the Iveri, unless we suppose the name Iveri to be Celtic and to mean "the fat people!" But we have seen that, in Irish tradition, the original Iverni were a pre-Celtic people, and we are under no necessity to discover a Celtic origin for their name.

For my part, granted that this people bore the name Iveri, changed afterwards into the adjectival form Iverni, I see no serious difficulty in supposing that this name was a local variant of Iberi, the name by which the people of Spain were known to the ancient Greeks and Romans.

Authorities on Irish archæology are agreed that the Early Stone Age is not exemplified in the most ancient remains of human occupation that have been discovered in Ireland. The explanation for this is supplied by the geologists. Some thousands of years ago, the conditions of perpetual snow and ice that at present prevail in the Arctic regions extended much farther into the temperate zones. The northern parts of Europe were covered with perpetual ice. Ireland lay entirely within this glacial zone. The southern limit of the ice ran through the south of England and eastward across the Continent. The time during which this southward extension of ice lasted is called the Glacial Period. Already before that time, Europe was inhabited by man, and the Early Stone Age or Palæolithic Age is held to have preceded the Glacial Period.

The condition of Ireland during that period was like the present condition of Greenland, under a heavy covering of ice formed by the accumulation of snow. By its own weight the ice kept moving from the mountains into the valleys and plains, and from the higher land level into the surrounding seas. Under its moving action, the solid rock-formation of the mountains was ground down and rounded off and scooped into hollows, and great sheets and ridges of stones, gravel, sand and boulder-clay were accumulated on the slopes and low grounds. It is evident that any traces of human life and habitation that may have existed before this process were not likely to be found after it.

The consequence is that the earliest traceable population of Ireland was Neolithic, i.e., belonged to the Late Stone Age. By the Stone Age is meant that time in which the use of metals was still unknown, and in which the most durable material of implements used by men was stone. Needless to say, they also used wood, bone, and any other material that came to hand. The Late Stone Age is distinguished from the Early Stone Age by the use of polished and finely shaped stone implements.

In England, according to eminent authorities already quoted, the descendants of Palæolithic Man survived and are still the prevalent type. In Ireland, they did not survive, and whatever Palæolithic blood is in our veins to-day is due to immigration. Regarding the Neolithic population of Ireland, whatever is to be said belongs rather to archæology than to history. In Britain, we are told, the Neolithic population consisted of at least three distinct races, one which had remained there from Palæolithic times, and two new races, or rather a mixture of two races, which came in from the Continent. One sees how futile it is to attempt to fix upon such a population a name like Iberian. It is assuming a knowledge which does not belong to us.