Ireland lies to the northwest of continental Europe and is surrounded by hundreds of islands and islets. To the east of Ireland is Great Britain, separated from it by the Irish Sea. The partition of Ireland between the Republic of Ireland, which covers just under five-sixths of the island, and Northern Ireland, a part of the United Kingdom, which covers the remainder and is located in the northeast of the island.
Relatively low-lying mountains surrounding a central plain epitomise Ireland's geography with several navigable rivers extending inland. The island has lush vegetation, a product of its mild but changeable oceanic climate, which avoids extremes in temperature. Thick woodlands covered the island until the 17th century. Today, it is the most deforested area in Europe. There are twenty-six extant mammal species native to Ireland.
A Norman invasion of Ireland in the Middle Ages gave way to a Gaels Resurgence in the 13th century.
Over sixty years of Tudor conquest of Ireland led to English dominion after 1603. In the 1690s, a system of Protestant Ascendancy was designed to materially disadvantage the Catholic majority and Protestant dissenters, and was extended during the 18th century. A Irish War of Independence in the early 20th century led to the Partition of Ireland, creating the Irish Free State, which became increasingly sovereign over the following decades. Northern Ireland remained a part of the United Kingdom and saw 'the troubles'. This subsided following Good Friday Agreement in 1998.
Irish culture has had a significant influence on other cultures, particularly in the fields of literature and, to a lesser degree, science and education. A strong Irish culture exists, as expressed for example through Gaelic games, Irish music and the Irish language, alongside a common Western culture, such as contemporary music and drama, and sports such as soccer, Rugby football and golf, and the English language.