Published in London in 1837, the Dictionary marked a new and significantly higher standard in such accounts of Ireland. Apart from The Parliamentary Gazetteer of Ireland published in 1845, it has not been superseded.
Lewis relied on the information provided by local contributors and on the earlier works published such as Coote's Statistical Survey (1801), Taylor and Skinner's Maps of the Road of Ireland (1777), Pigot's Trade Directory (1824) and other sources. He also used the various parliamentary reports and in particular the census of 1831 and the education returns of the 1820s and early 1830s. Local contributors were given the proof sheets for final comment and revision. The names of places are those in use prior to the publication of the Ordnance Survey Atlas in 1838. Distances are in Irish miles (the statute is 0.62 of an Irish mile).
The dictionary gives a unique picture of Ireland before the Great Famine.
These pages cover the then civil parishes of County Down.