Claim: Frank Sinatra performed in the most populated southern city.
Evidence: Sinatra 's professional career had stalled by the early 1950s , and he turned to Las Vegas , where he became one of its best known performers as part of the Rat Pack.
Las Vegas -LRB- -LSB- lɑːs_ˈveɪɡəs -RSB- , Spanish for `` The Meadows '' -RRB- , officially the City of Las Vegas and often known simply as Vegas , is the 28th-most populated city in the United States , the most populated city in the state of Nevada , and the county seat of Clark County.