In my Review of the Censuses from the turn of the 20th Century* - 1901 for IRELAND, ENGLAND, SCOTLAND AND CANADA, and 1900 for the UNITED STATES, I came across 35 Surname Variants of KERNAGHAN and these are listed below. (Note: the Documentation for the respective 1901 Censuses of AUSTRALIA and NEW ZEALAND were destroyed upon analysis completion).
Displayed on the Webpage 1900 /01 Census Distribution are 2 TABLES (with some brief Observations), each Table recording SURNAME VARIANT Distributions, as follows:
1901 BRITISH ISLES by Country (IRELAND, SCOTLAND and ENGLAND)
1901 CANADA and 1900 USA
It was interesting to observe the marked difference in the Surname Variants distribution of the KERNAGHAN surname between the OLD WORLD and the NEW WORLD.
The bar chart table above displays the Distribution of the Name Variants from the five Country censuses combined, which total 4,469 persons overall.
The name CARNAHAN dominates this by virtue of a 2,666 count, almost exclusively in the USA and CANADA. The second largest Name count is KERNAGHAN with 614 persons, a good majority being in IRELAND. These 2 Surnames alone account for 75% of the Kernaghan Surname Variant population from the 1900 / 01 Censuses.