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Since before recorded history of Ireland there have been countless Ireland Invasions.

Book of Invasions: The Mytho-Historical Text About Those Who Came to Conquer Ireland


Written records of the history of Ireland did not appear until the Middle Ages. As a result, much of the early history of Ireland is shrouded in mystery. Megalithic tombs and other structures dot the landscape and archaeologists have little certainty of who made them and why. Although Medieval Irish historians did not know much about what happened before the arrival of Christianity, they did try to investigate the question. One of these attempts is the Book of the Taking of Ireland.

Origins of Book of the Taking of Ireland

The Book of the Taking of Ireland, also called the Book of Invasions, is a mytho-historical text written by an unknown author in the 11th century AD. It recounts a series of invasions in which multiple waves of people-groups invade Ireland over several thousand years. The text seems to draw inspiration both from Celtic Mythology and from the Bible. Several of the characters in the book are descendants of Biblical figures such as Noah and Japheth. The flood is also mentioned. It may also have been influenced by Greek mythology since the book references Greece multiple times.

Page from the Book of Invasions of Ireland. (Soerfm / Public Domain)

Page from the Book of Invasions of Ireland. (Soerfm / Public Domain)

Although the book is mostly legend, it is possible that it may contain grains of historical truth, particularly with the last two major invasions mentioned in the book, the Tuatha De Dannan and the Milesians.

The First Invasion of Ireland – Cesair

According to the book, the earliest settlers of Ireland were led by a woman named Cesair. Cesair was a close relative of Noah who along with fifty other women and three men settled Ireland just forty days before the flood. This colony did not last long. They all died by the time that the flood took place.

The Second Invasion of Ireland – Partholon

The second wave of people to settle Ireland came about 300 years later and was led by a man named Partholon. Partholon came with eight other travelers, four men and four women. Once they arrived, they got to work clearing plains, cutting down forests, and driving away wild beasts to tame the land of Ireland and make it a civilized place. Partholon’s descendants, the Partholonians, flourished for 300 years. However, they did end up getting into conflicts with the Fomorians, a monstrous quasi-human race. The Fomorians are described by various sources as either having one arm, one leg, and one eye or having the body of a man and the head of a goat. In some accounts, though, they are also described as being strikingly beautiful. After about three centuries, the Partholonians met a tragic end when they were wiped out by a plague.

The Partholonians, the second invaders of Ireland. ( Foinse Laistigh / YouTube)

The Partholonians, the second invaders of Ireland. ( Foinse Laistigh / YouTube)

The Third Invasion of Ireland – Nemedh

After the extinction of the Partholonians, Ireland was once again uninhabited for 30 years until the arrival of Nemedh. Nemedh and his family came from the area around Greece. At first, the Nemedians prospered in Ireland. They built forts and cleared plains, but after a while, the Fomorians noticed that they had new potential victims in Ireland and began to harass the Nemedians.

"Tuan watches Nemed", an illustration of Tuán watching the Nemedians arrive in Ireland. (Fæ / Public Domain)

"Tuan watches Nemed", an illustration of Tuán watching the Nemedians arrive in Ireland. (Fæ / Public Domain)

Initially, the Nemedians did well in driving back the Fomorian onslaught. They won several major battles, but eventually a plague struck the Nemedians, wiping out two thousand. After this, the Nemedians were significantly weakened because of their loss in number. They soon fell under subjugation to the Fomorians.

Eventually, the Nemedians invaded the island homeland of the Fomorians and were able to besiege the Fomorians in their tower. This battle however decimated the Nemedian population. By the end of the battle, there were only about 30 Nemedians left. Many of them fled to Greece while a few of them left for Britain and northern Europe. Those in northern Europe are said to have eventually become the Tuatha De Dannan and those in Britain became the Britons. This was the end of the original Nemedians.

The Fourth Invasion of Ireland – the Fir Bolgs

The Nemedians who fled to Greece ended up becoming enslaved by the locals. After about 230 years of this, they were finally able to revolt and escape back to Ireland. When they arrived in Ireland, it was once again uninhabited. The Fir Bolgs are said to have divided up the island into five different regions each ruled by a chieftain.

Ambassadors of the Fir Bolg and Tuatha Dé Danann meeting before the Battle of Moytura. (Fæ / Public Domain)

Ambassadors of the Fir Bolg and Tuatha Dé Danann meeting before the Battle of Moytura. (Fæ / Public Domain)

The Fifth Invasion of Ireland – the Tuatha De Dannan

Another group of Nemedians settled northern Europe and became the Tuatha De Dannan. The Tuatha De Dannan returned to Ireland later. According to legend, the Tuatha De Dannan excelled in science, magic, and civilization. The Tuatha De Dannan are also believed to be the basis for later Christian legends about fairies.

The Tuatha Dé Danann as depicted in John Duncan's ‘Riders of the Sidhe’. (Thomas Gun / Public Domain)

The Tuatha Dé Danann as depicted in John Duncan's ‘Riders of the Sidhe’. (Thomas Gun / Public Domain)

The Sixth Invasion of Ireland – the Milesians

The Milesians are the final invaders identified as direct ancestors of the Gaels and the modern-day Irish. After a series of battles, the Milesians drove the Tuatha De Dannan underground. It is in this way that the earlier invaders are connected to Irish legends of little people living beneath hills and stones.

"The Coming of the Sons of Miled", illustration in Rolleston's Myths & Legends of the Celtic Race. (Fæ / Public Domain)

"The Coming of the Sons of Miled", illustration in Rolleston's Myths & Legends of the Celtic Race. (Fæ / Public Domain)

Legacy of the Invasions of Ireland

It is far from clear how much actual history is in the book. It is likely that most of it is a mixture of Celtic Mythology and legends from later Christian times. On the other hand, there may be some kernels of truth. The story of the interaction between the Milesians and the Tuatha De Dannan may reflect real aspects of the contact between the first Iron Age Celts to come to Ireland and the pre-Celtic Neolithic and Bronze Age inhabitants of Ireland most likely responsible for the megalithic monuments that are scattered across the island.

Nonetheless, the book is probably most useful in showing how Christian and pre-Christian Celtic thought were woven together to make a single narrative for the origin of the Irish that was both Celtic and Christian.

Top image: Since before recorded history of Ireland there have been countless Ireland Invasions. Source: Björn Alberts / Adobe.

By Caleb Strom


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Caleb Strom's picture


Caleb Strom is currently a graduate student studying planetary science. He considers himself a writer, scientist, and all-around story teller. His interests include planetary geology, astrobiology, paleontology, archaeology, history, space archaeology, and SETI.

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