Little Ireland is not marked on The Map, which is not known for its fine detail anyway. It could lie almost anywhere, as the Celts were known to have migrated from, roughly, Asia Minor northwest up to the British Isles, and had left pockets of identifiable culture all along that path. The fact that it's called "Little Ireland" with a ruling O'Hara family, however, implies that a group left Ireland (or The Irelands) and retraced ancestral steps, bringing their later-version culture with them.
That Little Ireland was able to build itself into a sufficiently powerful entity (probably due to the Sparkiness of the rulers) to get the Baron's attention implies an admirable amount of tenacity and determination, no matter its geographical size.
- ↑ Little Ireland is never mentioned directly in the Girl Genius comic. Most of what scant "official" information about Little Ireland exists is from sources outside the canon, strictly speaking. The fact that Sleipnir O’Hara comes from there is mentioned in the Girl Genius Complete List of Absolutely Everybody! in her capsule biography, where it states, "Sleipnir's father is a ruling Spark in the region of Wulfenbach's Europa informally termed 'Little Ireland.'"