One of the earliest and most enduring imprints of mosaic in Ireland can be found in prestigious public and ecclesiastical buildings adorned in the late 19th and early 20th centuries. Notably, the celebrated Manchester-based firm of Ludwig Oppenheimer Ltd was responsible for laying the mosaic floors in important cultural institutions such as the National Museum of Ireland — Archaeology in Dublin. These classical floors, featuring mythological and symbolic scenes, were largely forgotten under layers of flooring until they were cleaned and restored in recent years, re-revealing this elegant chapter of Ireland’s decorative legacy. While much of the early mosaic work in Ireland involved imported expertise, the mid-20th century marked a turning point with the emergence of home-grown mosaic craft. In County Roscommon, a thriving local mosaic industry was nurtured from the 1950s onwards when Irish Mosaics was established and skilled artisans, including Italian craftsmen, began producing vibrant geometric and artistic mosaics for shopfronts, pubs, and public commissions. Today, Roscommon’s mosaic heritage — celebrated in local photo-books and public art initiatives — stands as a testament to a uniquely Irish adaptation of the medium, one that blended international technique with regional creativity. Beyond towns and civic buildings, mosaic art continues to play a powerful role in places of worship and pilgrimage. At Our Lady’s Basilica in Knock, County Mayo, an extraordinary mosaic depicting the 1879 Apparition was unveiled behind the sanctuary following a major refurbishment. Crafted by artisans over hundreds of thousands of tesserae and designed in collaboration with Irish artist PJ Lynch, this large-scale work is among the most significant contemporary mosaic installations in Ireland, drawing both spiritual and artistic admiration.