The island of Ireland was formed about 10 thousand years B.C. when the polar ice cap melted and the sea level rose. The resulting narrow canal cut off Ireland from the southwest of Scotland. Ireland was isolated from mainland Europe about 6 thousand years before Britain became an island.
During the Pleistocene Ice Age, Ireland was covered with an ice sheet up to 300 meters thick, which crushed stones and bones under its weight and destroyed all possible traces of early hominid or human settlements. Human remains, dating back to the time of the last glaciation, were found in the extreme south of Britain, much of which remained uncovered by glacier.
During the Last Glacial Maximum in the Upper Paleolithic, about 16 thousand years B.C. Ireland was a tundra. Midland General Glaciation covered about two thirds of Ireland with drifting ice sheets. The climate was unfavorable for most European plants and animals, and human habitation during this period is considered unlikely.
In the period 15500 – 10000 B.C. there was warming, as a result of which nomadic hunter-gatherers began to penetrate into the northern parts of Europe. As can be seen from the data of genetics and the remnants of the fauna, the wave of migrants came from southwestern Europe, probably from the French-Cantabrian region. Of the animals in the preboreal period, the reindeer, and the tour first entered the north first. As can be seen from a number of sites dating back to a period older than 10,000 years ago, found, for example, in Sweden, people could use the edges of the glaciers as places from which they could hunt migratory game.
These factors and environmental changes have led to the fact that people began to colonize the most northern ice-free territories of Europe with the onset of the Holocene, including the territories closest to Ireland.
There is no evidence of people in Ireland during this period, except for one site dated 11 thousand years B.C. discovered on the east coast of the Irish Sea, whose inhabitants fed on marine food, including shellfish. Perhaps people really penetrated into Ireland, but its resources seemed to them scarce, except for what could be obtained on the coast.
As the northern glaciers retreated, the sea level rose, and the water penetrated the inland sea, which was in place of the modern Irish Sea. The outflow of fresh water and the associated sea level rise between the Irish and Celtic Seas was delayed, although it did not stop the penetration of flora and fauna from Continental Europe through Ireland.
Mesolithic
The bones of animals from the caves of Alice and Gwendolen in Clare County in the west of Ireland dated by ancient people are dated by radiocarbon analysis by an age of 12.5 thousand years.
On the territory of Ireland, the last glaciation ended about 10 thousand years B.C. The human colonization of Ireland began around 8000 – 7000 years B.C. It is assumed that the earliest settlers migrated to the islands from the territory of Britain through the Straits of Moyle and the St George Strait. The Mesolithic site at Mount Sandel in the north of Ireland dates back to 10 thousand years.
The earliest monuments of human presence in Ireland after the retreat of glaciers date back to between 8,000 and 7,000. B.C. The settlements of Mesolithic hunter-gatherers are found in several places scattered across the territory of Ireland: Mount Sandel in the county of Londonderry; Woodpark in Sligo County; in the estuary of the river Shannon; Lough Boora in Offaly; Curran in Antrim County; as well as several in Munster. It is assumed that the settlers originally colonized the north-east of the country, having got there from Scotland. Although at that time the sea level was lower than it is now, by that time Ireland may already have been an island, and the settlers got there by boat. The arrival hypothesis on boats looks quite probable in light of the fact that most of the Mesolithic settlements in Ireland were located on the coast. Obviously, the Mesolithic inhabitants of Ireland were a marine life and depended on sea food sources. To some extent, the marine life was imposed on them by the surrounding natural conditions, since even after the disappearance of the ice sheet, centuries passed before the permafrost disappeared from the soil and it was covered with vegetation.
The diet of hunters-gatherers of the Mesolithic was varied and consisted of seafood, poultry, wild pigs, hazelnuts, etc. There are no deer habitats in Ireland in the Mesolithic era; it is assumed that the reindeer first appeared here at the beginning of the Neolithic. People hunted with spears, arrows and harpoons with small flint tips, microliths, and supplemented their diet with a collection of nuts, fruits and berries. They dwelt in the seasonal dwellings that they built, stretching the skins of animals on wooden frames. Foci for cooking were located outside the dwellings. The population of Ireland in the Mesolithic era, apparently, did not exceed several thousand people.
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