The National Museum of Ireland is Ireland's leading museum institution, with a strong emphasis on national and some international archaeology, Irish history, Irish art, culture, and natural history. It has three branches in Dublin, the archaeology and natural history museums adjacent on Kildare Street and Merrion Square, and a newer Decorative Arts and History branch at the former Collins Barracks, and the Country Life museum in County Mayo.

The history of Irish art starts around 3200 BC with Neolithic stone carvings at the Newgrange megalithic tomb, part of the Brú na Bóinne complex which still stands today, County Meath. In early-Bronze Age Ireland there is evidence of Beaker culture and a widespread metalworking. Trade-links with Britain and Northern Europe introduced La Tène culture and Celtic art to Ireland by about 300 BC, but while these styles later changed or disappeared under the Roman subjugation, Ireland was left alone to develop Celtic designs: notably Celtic crosses, spiral designs, and the intricate interlaced patterns of Celtic knotwork.