The phrase Viva Las Vegas has been around for a long time, but it didn’t become popular until Elvis Presley started using it in the 1960s.

The city of Las Vegas was given its name in the early 1800s by a Spanish explorer named Rafael Rivera.  Explorers would often stop in this area to get water when traveling through the Mojave Desert.  He gave Las Vegas its name because parts of the Las Vegas Valley contain natural water springs and wells.  At the time, these springs were surrounded by vegetation, which made the valley look like a meadow.  In Spanish, the exact translation of “Viva Las Vegas” is Long Live the Meadows.

Elvis Presley starred in the 1964 film Viva Las Vegas (directed by George Sidney).  The song was written by Doc Pomus and Mort Shuman as the title song for the film. It was recorded on July 10, 1963 and released as a single in 1964 with the B-side "What'd I Say" (written by Ray Charles) from the same film,

"Viva Las Vegas" charted separately from its B-side, reaching No. 29 on the Billboard Hot 100 pop singles chart.  The Elvis version of "What'd I Say" peaked at No. 21, the two sides of the record showing equal appeal.

The movie was about a race car driver, Lucky Jackson (played by Elvis) who comes to Las Vegas to take part a Grand Prix Race.  Along the way his car needed a new engine, but when he is pushed into a swimming pool by Rusty Martin (Ann-Margret), the hotel swimming instructor as well as casino singer and dancer, he loses the money intended for his new engine.                                                                                                                      Lucky then must work as a waiter at the hotel to pull together the cash for his engine.  He ends up entering the hotel’s talent competition, performing the title song, to compete for the cash prize. Elvis’s character ends up winning the race and marrying Rusty.

In the years since its first release, the song has become one of Presley's most recognized numbers. the song appeared in countless movies and TV sitcoms and as a reference to the city of Las Vegas.

His movie performance of Viva Las Vegas is classic Elvis but one that he never performed in front of a live audience.

Viva Las Vegas was the most successful of the 31 films Elvis starred in, returning more than $5 million to MGM Studios on an investment of less than $1 million.

Various Sources