Ireland is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially named Irelanda sovereign state covering five-sixths of the island) and Northern Ireland (part of the United Kingdomcovering the remaining sixth). It is separated from Great Britain to its east by the North Channel, the Irish Sea, and St George's Channel. Ireland is the second-largest island of the British Isles, the third-largest in Europe, and the twentieth-largest in the world. As of 2022, the population of the entire island is just over 7 million, with 5.1 million in the Republic of Ireland and 1.9 million in Northern Ireland, ranking it the second-most populous island in Europe after Great Britain.
The geography of Ireland comprises relatively low-lying mountains surrounding a central plain, with several navigable rivers extending inland. Much of Ireland was woodland until the end of the Middle Ages. Today, woodland makes up about 10% of the island, compared with a European average of over 33%, with most of it being non-native conifer plantations. Its lush vegetation is a product of its mild climate, which is influenced by the Atlantic Ocean and thus very moderate, and winters are milder than expected for such a northerly area, although summers are cooler than those in continental Europe. Rainfall and cloud cover are abundant.
Gaelic Ireland had emerged by the 1st century AD. The island was Christianised from the 5th century onwards. During this period Ireland was divided amongst petty kings, who in turn served under the kings of the traditional provinces (; ) vying for dominance and the title of High King of Ireland. Between the late 8th and early 11th centuries, Viking raids and settlement took place culminating in the Battle of Clontarf on 23 April 1014 which resulted in the end of Viking power in Ireland. Following the 12th-century Anglo-Norman invasion, England claimed sovereignty. However, English rule did not extend over the whole island until the 16th–17th century Tudor conquest, which led to colonisation by settlers from Britain. In the 1690s, a system of Protestant English rule was designed to materially disadvantage the Catholic majority and Protestant dissenters, and was extended during the 18th century. With the Acts of Union in 1801, Ireland became a part of the United Kingdom. The Great Famine of the 1840s saw the population fall by over 20%, through death and emigration. A war of independence in the early 20th century was followed by the partition of the island, leading to the creation of the Irish Free State, which became increasingly sovereign over the following decades until it declared a republic in 1948 (Republic of Ireland Act, 1948) and Northern Ireland, which remained a part of the United Kingdom. Northern Ireland saw much civil unrest from the late 1960s until the 1990s. This subsided following the Good Friday Agreement in 1998. In 1973, both the Republic of Ireland and the United Kingdom, with Northern Ireland as part of it, joined the European Economic Community. Following a referendum vote in 2016, the United Kingdom, Northern Ireland included, left the European Union (EU) in 2020. Northern Ireland was granted a limited special status and allowed to operate within the EU single market for goods without being in the European Union.
Irish culture has had a significant influence on other cultures, especially in the field of literature. Alongside mainstream Western culture, a strong indigenous culture exists, as expressed through Gaelic games, Irish music, Irish language, and Irish dance. The island's culture shares many features with that of Great Britain, including the English language, and sports such as association football, rugby, horse racing, golf, and boxing.
Name
The names Ireland and both derive from Old Irish Ériu, which in turn comes from Proto-Celtic ɸīweriyū meaning "fertile soil". The Classical Latin name for the island of Ireland, Ivernia, also comes from this same root, and it remains a popular, poetic synonym for the island (usually respelt "Hibernia", under the influence of hibernum, the Latin word for "winter").
History
Prehistoric Ireland
During the last glacial period, and until about 16,000 BC, much of Ireland was periodically covered in ice. By 14,000 BC this ice bridge existed only between Northern Ireland and Scotland and by 12,000 BC Ireland was completely separated from Great Britain. Later, around 6,100 BC, Great Britain became separated from continental Europe. Until recently, the earliest evidence of human activity in Ireland was dated at 12,500 years ago, demonstrated by a butchered bear bone found in a cave in County Clare. In 2021, a reindeer bone with chop marks, which had been found in Castlepook Cave near Doneraile, County Cork in the early twentieth century during Richard J. Ussher's excavations, was dated to 33,000 years ago by Dr Ruth Carden, a paleozoologist from the School of Archaeology in University College Dublin, pushing back the earliest signs of human activity by 20,000 years.
By about 8,000 BC, more sustained occupation of the island has been shown, with evidence for Mesolithic communities around the island.
Some time before 4,000 BC, Neolithic settlers introduced cereal cultivars, domesticated animals such as cattle and sheep, built large timber buildings, and stone monuments. Field systems were developed in different parts of Ireland, including at the , that has been preserved beneath a blanket of peat in present-day Tyrawley in northwest Mayo. An extensive field system, arguably the oldest in the world, consisted of small divisions separated by dry-stone walls. The fields were farmed for several centuries between 3,500 BC and 3,000 BC. Wheat and barley were the principal crops.
The Bronze Age began around 2,500 BC, with technology changing people's everyday lives during this period through innovations such as the wheel, harnessing oxen, weaving textiles, brewing alcohol and metalworking, According to John T. Koch and others, Ireland in the Late Bronze Age was part of a maritime trading culture called the Atlantic Bronze Age that also included Britain, western France and Iberia, and that this is where Celtic languages developed. This contrasts with the traditional view that their origin lies in mainland Europe with the Hallstatt culture.
thumb|left|upright|[[Uragh Stone Circle|The Uragh Stone Circle, a Neolithic stone circle in Tuosist, close to Gleninchaquin Park, County Kerry]]
The long-standing traditional view is that the Celtic language, Ogham script and culture were brought to Ireland by waves of invading or migrating Celts from mainland Europe. This theory draws on the Lebor Gabála Érenn, a medieval Christian pseudo-history of Ireland, along with the presence of Celtic culture, language and artefacts found in Ireland such as Celtic bronze spears, shields, torcs and other finely crafted Celtic associated possessions. The theory holds that there were four separate Celtic invasions of Ireland. The Priteni were said to be the first, followed by the Belgae from northern Gaul and Britain. Later, Laighin tribes from Armorica were said to have invaded Ireland and Britain more or less simultaneously. Lastly, the Milesians (Gaels) were said to have reached Ireland from either northern Iberia or southern Gaul. It was claimed that a second wave named the Euerni, belonging to the Belgae people of northern Gaul, began arriving about the 6th century BC. They were said to have given their name to the island.
The theory was advanced in part because of the lack of archaeological evidence for large-scale Celtic immigration, though it is accepted that such movements are notoriously difficult to identify. Historical linguists are skeptical that this method alone could account for the absorption of Celtic language, with some saying that an assumed processual view of Celtic linguistic formation is 'an especially hazardous exercise'. Genetic lineage investigation into the area of Celtic migration to Ireland has led to findings that showed no significant differences in mitochondrial DNA between Ireland and large areas of continental Europe, in contrast to parts of the Y-chromosome pattern. When taking both into account, a study concluded that modern Celtic speakers in Ireland could be thought of as European "Atlantic Celts" showing a shared ancestry throughout the Atlantic zone from northern Iberia to western Scandinavia rather than substantially central European.
In 2012, research showed that the occurrence of genetic markers for the earliest farmers was almost eliminated by Beaker-culture immigrants: they carried what was then a new Y-chromosome R1b marker, believed to have originated in Iberia about 2,500 BC. The prevalence amongst modern Irish men of this mutation is a remarkable 84%, the highest in the world, and closely matched in other populations along the Atlantic fringes down to Spain. A similar genetic replacement happened with lineages in mitochondrial DNA. This conclusion is supported by recent research carried out by the geneticist David Reich, who says: "British and Irish skeletons from the Bronze Age that followed the Beaker period had at most 10 per cent ancestry from the first farmers of these islands, with other 90 per cent from people like those associated with the Bell Beaker culture in the Netherlands." He suggests that it was Beaker users who introduced an Indo-European language, represented here by Celtic (i.e. a new language and culture introduced directly by migration and genetic replacement). In his map of Ireland in his later work, Geography, Ptolemy refers to Ireland as Iouernia and to Great Britain as Albion. These names were likely to have been the local names for the islands at the time. The earlier names, in contrast, were likely to have been coined before direct contact with local peoples was made.
The Romans referred to Ireland by this name too in its Latinised form, Hibernia, or Scotia. Ptolemy records 16 nations inhabiting every part of Ireland in 100 AD. The relationship between the Roman Empire and the kingdoms of ancient Ireland is unclear. However, finds of Roman coins have been made, for example at the Iron Age settlement of Freestone Hill near Gowran and Newgrange.
Ireland continued as a patchwork of rival kingdoms; however, beginning in the 7th century, a concept of national kingship gradually became articulated through the concept of a High King of Ireland. Medieval Irish literature portrays an almost unbroken sequence of high kings stretching back thousands of years, but some modern historians believe the scheme was constructed in the 8th century to justify the status of powerful political groupings by projecting the origins of their rule into the remote past.
All of the Irish kingdoms had their own kings but were nominally subject to the high king. The high king was drawn from the ranks of the provincial kings and ruled also the royal kingdom of Meath, with a ceremonial capital at the Hill of Tara. The concept did not become a political reality until the Viking Age and even then was not a consistent one. Ireland did have a culturally unifying rule of law: the early written judicial system, the Brehon Laws, administered by a professional class of jurists known as the brehons.
The Chronicle of Ireland records that in 431, Bishop Palladius arrived in Ireland on a mission from Pope Celestine I to minister to the Irish "already believing in Christ". The same chronicle records that Saint Patrick, Ireland's best known patron saint, arrived the following year. There is continued debate over the missions of Palladius and Patrick, but the consensus is that they both took place and that the older druid tradition collapsed in the face of Christianity. Irish Christian scholars excelled in the study of Latin and Greek learning and Christian theology. In the monastic culture that followed the Christianisation of Ireland, Latin and Greek learning was preserved in Ireland during the Early Middle Ages in contrast to elsewhere in Western Europe, where the Dark Ages followed the Fall of the Western Roman Empire.
thumb|right|A folio of the [[Book of Kells showing Christ enthroned]]
The arts of manuscript illumination, metalworking and sculpture flourished and produced treasures such as the Book of Kells, ornate jewellery and the many carved stone crosses that still dot the island today. A mission founded in 563 on Iona by the Irish monk Saint Columba began a tradition of Irish missionary work that spread Celtic Christianity and learning to Scotland, England and the Frankish Empire on continental Europe after the fall of Rome. These missions continued until the late Middle Ages, establishing monasteries and centres of learning, producing scholars such as Sedulius Scottus and Johannes Eriugena and exerting much influence in Europe.
From the 9th century, waves of Viking raiders plundered Irish monasteries and towns. These raids added to a pattern of raiding and endemic warfare that was already deep-seated in Ireland. The Vikings were involved in establishing most of the major coastal settlements in Ireland: Dublin, Limerick, Cork, Wexford, Waterford, as well as other smaller settlements.
Norman and English invasions
thumb|Remains of the 12th-century [[Trim Castle in County Meath, the largest Norman castle in Ireland]]
On 1 May 1169, an expedition of Cambro-Norman knights, with an army of about 600 men, landed at Bannow Strand in present-day County Wexford. It was led by Richard de Clare, known as 'Strongbow' owing to his prowess as an archer. The invasion, which coincided with a period of renewed Norman expansion, was at the invitation of Dermot Mac Murrough, King of Leinster.
In 1166, Mac Murrough had fled to Anjou, France, following a war involving Tighearnán Ua Ruairc, of Breifne, and sought the assistance of the Angevin King Henry II, in recapturing his kingdom. In 1171, Henry arrived in Ireland in order to review the general progress of the expedition. He wanted to re-exert royal authority over the invasion which was expanding beyond his control. Henry successfully re-imposed his authority over Strongbow and the Cambro-Norman warlords and persuaded many of the Irish kings to accept him as their overlord, an arrangement confirmed in the 1175 Treaty of Windsor.
The invasion was legitimised by reference to provisions of the alleged Papal Bull Laudabiliter, issued by an Englishman, Adrian IV, in 1155. The document apparently encouraged Henry to take control in Ireland in order to oversee the financial and administrative reorganisation of the Irish Church and its integration into the Roman Church system. Some restructuring had already begun at the ecclesiastical level following the Synod of Kells in 1152. There has been significant controversy regarding the authenticity of Laudabiliter, and there is no general agreement as to whether the bull was genuine or a forgery. Further, it had no standing in the Irish legal system.
thumb|left|Political boundaries in Ireland in 1450, before the [[plantations of Ireland|plantations]]
In 1172, Pope Alexander III further encouraged Henry to advance the integration of the Irish Church with Rome. Henry was authorised to impose a tithe of one penny per hearth as an annual contribution. This church levy, called Peter's Pence, is extant in Ireland as a voluntary donation. In turn, Henry assumed the title of Lord of Ireland which Henry conferred on his younger son, John Lackland, in 1185. This defined the Anglo-Norman administration in Ireland as the Lordship of Ireland. When Henry's successor, Richard the Lionheart died unexpectedly in 1199, John inherited the crown of England and retained the Lordship of Ireland. Over the century that followed, Norman feudal law gradually replaced the Gaelic Brehon Law across large areas, so that by the late 13th century the Norman-Irish had established a feudal system throughout much of Ireland. Norman settlements were characterised by the establishment of baronies, manors, towns and the seeds of the modern county system. A version of Magna Carta (the Great Charter of Ireland), substituting Dublin for London and the Irish Church for, the English church at the time, the Catholic Church, was published in 1216 and the Parliament of Ireland was founded in 1297.
Gaelicisation
From the mid-14th century, after the Black Death, Norman settlements in Ireland went into a period of decline. The Norman rulers and the Gaelic Irish elites intermarried and the areas under Norman rule became Gaelicised. In some parts, a hybrid Hiberno-Norman culture emerged. In response, the Irish parliament passed the Statutes of Kilkenny in 1367. These were a set of laws designed to prevent the assimilation of the Normans into Irish society by requiring English subjects in Ireland to speak English, follow English customs and abide by English law.
By the end of the 15th century, central English authority in Ireland had all but disappeared, and a renewed Irish culture and language, albeit with Norman influences, was again dominant. English Crown control remained relatively unshaken in an amorphous foothold around Dublin known as The Pale, and under the provisions of Poynings' Law of 1494, Irish Parliamentary legislation was subject to the approval of the English Privy Council.
Kingdom of Ireland
thumb|A 16th-century perception of Irish women and girls, illustrated in the manuscript "Théâtre de tous les peuples et nations de la terre avec leurs habits et ornemens divers, tant anciens que modernes, diligemment depeints au naturel". Painted by [[Lucas de Heere|Lucas d'Heere in the 2nd half of the 16th century. Preserved in the Ghent University Library.]]
The title of King of Ireland was re-created in 1542 by Henry VIII, King of England, of the Tudor dynasty. English rule was reinforced and expanded in Ireland during the latter part of the 16th century, leading to the Tudor conquest of Ireland. A near-complete conquest was achieved by the turn of the 17th century, following the Nine Years' War and the Flight of the Earls.
This control was consolidated during the wars and conflicts of the 17th century, including the English and Scottish colonisation in the Plantations of Ireland, the Wars of the Three Kingdoms and the Williamite War. During the Irish Confederate Wars (1641–1653), Ireland experienced a catastrophic demographic collapse. Modern estimates suggest that approximately 20,000–30,000 soldiers died in combat, while an estimated 200,000 to over 300,000 civilians perished from war-related famine, disease, and displacement, with some contemporary estimates, such as those by Sir William Petty, suggesting even higher mortality figures. A further 50,000