From Latin viola ‘violet’. The name is relatively common in Italy and was used by Shakespeare in Twelfth Night, where most of the characters have Italianate names. Its modern use in English has been influenced by the vocabulary word denoting the flower.
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.)