Surname distribution maps for Cullens
Cullens in the 1881 Census
Cullens in the 21st Century
The maps, if available, show both where there are more people named Cullens and where they are most concentrated.
The darker the colour, the more people in that county are named Cullens.
The larger the dot, the greater the proportion of people in that county are named Cullens.
Hovering over the dots will give you the individual statistics for that county.