Where did the expression 'It ain't over til the fat lady sings' originate?

Until the Fat Lady Sings...A reference to Kate Smith, the proverbial "fat lady" who hailed the rise of the Philadelphia Flyers "Broadstreet Bullies" during the 1970s with her rousing renditions of "God Bless America." More Information:There are three basic possibilities for the origin of this phrase:

• Although some speculate that the phrase refers to a crass interpretation of opera or is attributable to women in southern church choirs, the phrase "It ain't over till the fat lady sings" actually refers to an actual "fat lady," Kate Smith, who was a large woman and a very popular singer and radio star from the 1930s to 1950s (Irving Berlin wrote God Bless America for her). In the 1950s, Kate had her own TV show, which ended right before the station went off the air for the night - thus, the TV broadcast day was not over until this particular fat lady sang her closing song. The phrase itself was later coined in Philadelphia, Pennsylvania during the 1970s. It originated when the Philadelphia Flyers of the day, called the "Broadstreet Bullies," amassed an impressive record on nights when Kate Smith's "God Bless America" was played over the loudspeaker system at the Spectrum. The flyers were nearly unbeaten in games when the song was played during the 1973-74 season, and Kate Smith herself appeared live for Game 6 of the 1974 Stanley Cup Finals when the underdog Flyers prevailed to win the cup over the heavily favored Boston Bruins. The Flyers had such success during games before which Kate smith sang that the phrase "It ain't over till the fat lady sings" was coined in Philadelphia.

No matter where it comes from, the saying means "you don't know how this is going to end until the final minute."

Yet more information:"The adage sounds like it sprung from the mouth of a weary opera patron, but it was actually coined by a sportswriter and broadcaster named Dan Cook.

"Cook covered the NBA's San Antonio Spurs in the 1970s. In 1978, the Spurs were playing the Washington Bullets in the playoffs and down three games to one. Cook, who had used the witticism once before in a column, repeated it on the air as a way to cheer up Spurs fans. Alas, despite making it close, the Spurs lost the series.

"Bullets coach Dick Motta apparently liked the saying and used it to motivate his own team. The Bullets went on to win the championship, proving that while "it's not over 'til the fat lady sings," sometimes inspirational clich�s are "too little, too late."

This explanation has allegedly been recorded in the Library of Congress By the way, I was alive during the Kate Smith days and also heard that attribution a few years later, but before Cook used it in the '70s. It makes more sense than the opera reference since many operas do not end with an aria by the strongest female diva, fat or not.