The fundamental geographical fact about Ireland is that it is an island; this fact has had tremendous impact on Ireland's history and character. No point on the island is more than 70 miles from the sea. For generations, the sea has represented food, danger, and hope for the Irish people. It has also meant isolation. Because of the difficulty of reaching them, islands tend to be more politically and culturally isolated than nations on larger landmasses. Ireland's position on the far western end of Europe has increased this isolation; contrast it with Sicily, an island of similar size but with a far more volatile history because of its location in the middle of the Mediterranean.
Map of Western Europe
The northwestern tip of Ireland is very close to Scotland; from ancient times, the people in northern Ireland and western Scotland have spent a lot of time with one another. St. Columcille went to the island of Iona, a part of Scotland that is a short boat ride from Ireland; from there he spread Christianity among the Scottish people. Ulster has always had a sizable Presbyterian Scottish population, called the “Scotch-Irish” or “Scots-Irish.”
England and Wales are slightly further away than Scotland, but they are still close. Ireland's proximity and geographical similarity to England made it an appetizing colony for Anglo-Normans. In more recent times, the Irish have found England a handy place to go for work, close enough that they can visit home regularly.
Ireland's other neighbors include France, Spain, and the Scandinavian countries. In the 1700s Wolfe Tone found France close enough to Ireland to make a military attack from there feasible. Spain is slightly farther than France, but not a bad boat trip; ancient Celts made the voyage more than 2,000 years ago, moving their culture from Spain to Ireland, and people have imported horses from Spain for hundreds of years. The Vikings from Norway and Denmark attacked both British Isles, which were conveniently close and offered lots of appetizing shoreline.
Ireland's isolation meant that Celtic culture could survive there after it was wiped out almost everywhere else. Ireland was a safe haven for Christian scholarship during the early Middle Ages, when the rest of Europe was a mess of barbarians and invasions. Even during World War II, Ireland used its physical isolation to maintain its political neutrality.