Retroactive nomenclature
Retroactive nomenclature is the telling of the earlier history of a person, place or thing while referring to said person, place or thing by a name that came into use at a later date.
Examples
Names
One easily understandable example of retroactive nomenclature is the tradition in many countries that a woman adopts the surname of the man she marries while remembering her "maiden name" as the way she was referred to her pre-marital days. Radio talk-show host Michael Medved once made the statement: "Hillary Clinton used to be conservative when I knew her in our college days." But in Hillary Rodham's college days she was not yet married to Bill Clinton; therefore there was no "Hillary Clinton" at that time. However, such a case as this is easily understood that he meant the woman who later became known as Hillary Clinton.
Similarly, the events of a future monarch's life are often recounted with the regnal name, as in "Queen Victoria was born in 1819." (Princess Alexandrina Victoria of Kent was born in 1819 and became queen in 1837.)
Chinese emperors are posthumously given temple names, used in most references to emperors from the Han to the Ming Dynasty. Most of these are agreed upon posthumously.
When people today read ancient histories, confusion sometimes results from the fact that in earlier ages historical characters changed their names more often than is common for people to do today, and ancient historians often told earlier stories using later names.
It is possible that King David's name during his boyhood and youth was Elhanan, and his father Jesse, likewise, had the earlier names of Jaare-Oregim and Jair. Although he was not known as "David" until later, one Biblical account (1 Samuel chapter 17) tells the story of his slaying the Philistine giant Goliath, while still calling him David. In 2 Samuel 21:19 he is called Elhanan.
Other
"Jew" originally meant a person from the nation of Judah (called "Judea" by the Roman Empire), which came into existence after the reign of king Solomon, when the nation of Israel was divided in two. Those from Israel prior to then – the Hebrew slaves in Egypt, as well as the Patriarchs from whom they descended – were not "Jews" in this technical sense, but Jewish historians still refer to these earlier ancestors as Jews.