Possibly from the Old Norse name Alvis meaning 'all wise', popularized in the American South.
Elvis is most often traced to old Germanic and possibly Old Norse naming traditions, with scholars linking it to elements suggesting "all-wise" or to names such as Alvis. It also appears in older forms in the British Isles, including the Irish saint's name Ailbe, which has sometimes been anglicized in related ways, though not all such connections are direct. Before the twentieth century, Elvis existed but was uncommon, appearing here and there in Scandinavian and English-speaking contexts without becoming a mainstream favorite.
It was recognizable, but not culturally dominant. That changed completely with Elvis Presley. Few names in modern history have been so thoroughly overtaken by a single bearer.
Presley transformed Elvis from a rare personal name into a global symbol of charisma, musical revolution, and American celebrity. His influence was so overwhelming that the name became almost mononymous, like a title. To say "Elvis" is usually to mean Presley, not just a person with that given name.
The name's sound helped: quick, bright, and unforgettable, with a swagger that matched the cultural force of rock and roll. As a result, the name's perception shifted in a way that is unusual even among famous-associated names. Elvis became glamorous, rebellious, Southern, musical, and deeply nostalgic all at once.
For some, it can feel almost too iconic to use, because it carries such a specific cultural image; for others, that is exactly its appeal. The name has appeared in films, songs, impersonation culture, and countless references to fame and performance. Elvis is therefore a lesson in how a name's destiny can be rewritten by popular culture: what may once have been an obscure old name became, through one extraordinary figure, a permanent piece of modern mythology.