Cognomen ケルン (Kern 
, Köln 
, ケルン) , in the entire world, is a widespread last name. The cognomen ケルン is habitual in Austria, where it is quite a common surname, Germany, and Slovenia (explore the name in all countries). In absolute terms, it is the most numerous in Germany, the United States, and Austria. Much less frequently, ケルン is the forename as well as the last name.