Dublin’s Natural History Museum is a uniquely preserved sliver of the past, an intact example of a nineteenth-century natural science collection. While its polished cases and stuffed animals show us what the museum looked like in its heyday, this book is the first detailed exploration of its early history, showing how and why it came into being, and what it meant in nineteenth-century Irish culture. From its earliest days as a small collection at the Royal Dublin Society to the gala inauguration of its new home on Merrion Square in 1857, everyone had an idea about what it was for, and how natural science would benefit Ireland. It was the first public museum in Ireland, a project of the RDS that was supported by central government as an educational venue, and was frequented by ordinary citizens and visitors as well as leading lights of natural science. Its history offers a view of science in Ireland showing that the museum was built over time by donations from citizens and scientific amateurs as well as professionals, and that Irish men of science shaped new knowledge from the raw material in the collections. Far from the aura of genteel nostalgia that continues to attract visitors today, the Natural History Museum of the nineteenth century was an active scientific institution with strong connections to the wider sphere of European science, and shows how participation in natural science was a form cultural activity for the people who engaged with the museum.