The National Museum of Ireland (Ard-Mhúsaem na hÉireann) 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 National Museum of Ireland descends from the amalgamation of parts of the collections of a number of Dublin cultural institutions from the 18th and 19th centuries, including primarily the Royal Dublin Society (RDS) and the Royal Irish Academy (RIA). The earliest parts of the collections are largely geological and mineralogical specimens, which the RDS collected as a means to improve the knowledge and use of such resources in Ireland. The establishment of the museum collections is generally deemed to have begun with the purchase of the collection of Nathanael Gottfried Leske in 1792.
One of the earliest iterations of the RDS museum was at Hawkins Street House, where the Leskean Cabinet was displayed along with a collection of casts and busts. This exhibition was open to the public between noon and 3pm, on Mondays, Wednesdays and Fridays. Aside from the exhibition, there was a lecture hall, laboratory and library. From here, the museum moved to Leinster House in 1815 when the RDS purchased it from the 3rd Duke of Leinster. Here the Leskean Cabinet continued to be displayed, along with newly accessioned collections from professor of mineralogy and geology, Charles Lewis Giescke, curiosities, and the Hibernicum which was a display of minerals and geological specimens from the island of Ireland.
Giescke was the first to refer to the museum as the "National Museum of Ireland", in 1832, in his catalogue of the entomology and ornithology specimens. After Giescke's death in 1833, John Scouler was appointed curator in 1834.