The champagne is flowing again at Castle Leslie, a fairy-tale 19th century estate in Ireland's County Monaghan. After languishing for years in a crumbling state of neglect, the place has reclaimed its former role as a playground for well-heeled eccentrics and sophisticated bohemians.
The Leslie clan can trace its lineage back to Attila the Hun and was granted what was originally a 45,000-acre (18,000 ha.) estate by King Charles II as thanks for helping to keep Oliver Cromwell at bay. Sir John Leslie built the castle itself in 1870, and invited all his pre-Raphaelite artist friends including...