Still, she found the wherewithal to take her self-styled choreography to the famous Amateur Night at the Apollo Theater in Harlem in 1934, but she lost her confidence when a pair of dancing sisters conquered the crowd. At a loss for what to do instead, Fitzgerald sang two Connee Boswell hits, "Judy" and "The Object of My Affection," and won first prize.
Saxophonist-bandleader Benny Carter was in the house that night and began championing her, leading Fitzgerald to earn a spot with drummer Chick Webb's band.
"You might say it was with Chick that I learned how to sing," Fitzgerald told me, her musical training up to the mid-1930s consisting of a few $5 piano lessons in which "I hardly learned a thing."
"Chick was the kind of person who had patience and understanding," continued Fitzgerald. "Now Chick didn't teach me any style. But he let me do what I felt, he let me sing the way he felt I could sing, and that's what started to make what Ella is today.
"Somehow I just fell in with the band."
The incontrovertible proof came in 1938, when Fitzgerald's recording of "A-Tisket, A-Tasket" became a national hit that put Webb's band on the map.
"We really didn't think anything special of that song, because it was just a new version of that kid's game, where they drop a handkerchief and run around each other," Fitzgerald said to me.
"But when I sang in Boston, it became an overnight hit, and it was a great beginning for us. Maybe it was so popular because everyone remembers playing the game as a kid."
Or maybe because the openness, warmth and simplicity of Fitzgerald's singing felt like a balm in troubled times. Still, unless you already know that's Fitzgerald singing, you might not connect her straightforward early work with the brilliant vocal flights yet to come.
It wasn't until Fitzgerald toured with Dizzy Gillespie's bebop big band, in the 1940s, that she developed the high-flying technical wizardry for which she eventually would be best known.
"After Chick, I used to go and jam with Dizzy, and that's how I learned my bop," Fitzgerald told me.
"Back then, they used to have places where you could just go and jam, you know? Although they'd be sort of seedy after-hours spots, it was still the place to be.
"So I used to follow Dizzy, travel a couple places with him, and I guess I was just thrilled with what was going on (in Gillespie's explosive ensemble), and I tried to do it.
"I just tried to do what I heard the horns in the band doing."
Fitzgerald, of course, wasn't the first to apply instrumental techniques to jazz vocals, Louis Armstrong essentially having launched the idiom in the 1920s with his recording of "Heebie Jeebies," and Cab Calloway taking it to new heights in the 1930s and after.
But no one before or since matched the velocity, pitch accuracy, vocal range or sheer creativity of Fitzgerald's scat singing, which ultimately transcended what any horn could do. Listen to her vocal invention on compositions such as "Flying Home" (1945) and "Oh, Lady Be Good" (1947), and you're hearing technical feats that astonish the ear to this day.
And still Fitzgerald wasn't done creating new paths in sound. Her landmark "Ella Fitzgerald Sings the Cole Porter Songbook," for Norman Granz's Verve records label, was a hit in the mid-1950s, spawned other Fitzgerald "Songbook" albums and made her a bona fide pop star.
"I always feel that Norman saved me, because a lot of the jazz clubs were closing at that time, so he had the idea that maybe I could sing something besides just straight jazz songs," Fitzgerald told me.
"And, bless him, he had the idea for me to try to do the songbooks, and I guess people were surprised to hear that I could sing something besides just pure jazz.
"I thank Norman so very much, otherwise, where would Ella be?"
And yet, despite all this, Fitzgerald was widely undervalued.
"Her voice is small and somewhat girlish ... as an interpreter of popular songs she is limited," noted the New Grove Dictionary of Jazz, adding — helpfully — that she is "unrivaled in her rendition of light material."
In part, I believe this perception was due to misguided comparisons to Billie Holiday, a tragedian whose stripped-down vocal style represented another expressive realm from Fitzgerald's — not better nor worse, just different. But Fitzgerald, too, could take listeners into dark places, as in her mournful recording of "Angel Eyes" (1957) or her disarmingly vulnerable "One for My Baby (and One More for the Road)" (1960).
In effect, some observers were so dazzled by Fitzgerald's technical prowess as to overlook the deeper content beneath it. Alas, high-toned virtuosity often has been unjustly derided in jazz circles, instrumental wizards such as pianists Art Tatum and Oscar Peterson and trumpeter Wynton Marsalis similarly castigated for their finesse — as if it diminished the "authenticity" of their music.
When Fitzgerald played that last Chicago-area concert, at age 74, she no longer conveyed the full voluptuousness of sound that once was her trademark. But to hear her stretch a melody to the breaking point in Fats Waller's "Ain't Misbehavin,'" leap multiple octaves in Kurt Weill's "Mack the Knife" and scat-sing exuberantly in Gillespie's "A Night in Tunisia" — meanwhile producing vocal clicks, pops, shouts and yowls — was to realize that her spirit of experimentation endured.
That's ultimately what made Fitzgerald pre-eminent among female jazz vocalists: the desire to continuously redefine her work, and the determination to build techniques that enabled her to do so.
"Through the years, when I look back and think about all I've been through, I sometimes ask myself, 'Was it worth it?'" Fitzgerald said in our conversation, perhaps contemplating two short-lived marriages (she had one adopted son, Ray Brown Jr., named for her second husband, the celebrated bassist).
"Then I look at all these things in my (California) home," she added, referring to her National Medal of Arts, multiple Grammys and honorary doctorate degrees.
"And I say to myself, 'Well, my gosh, maybe it was worth it.'
"I'm grateful to see all these awards and things, because it makes me feel like somebody loved me."
Millions still do.