Danish equivalent of Katherine. It was first introduced to the English-speaking world by Scandinavian settlers in America; it has been used in Britain only since the 1940s, but had become very popular by the 1960s.
English and Scottish: patronymic from the personal name John. As an American family name, Johnson has absorbed patronymics and many other derivatives of this name in continental European languages. (For forms, see Hanks and Hodges 1988.)