Some performers are so intense, so inimitable, that trying capture their appeal in mere words is the proverbial exercise in futility. For example, David Bowie probably came closest to summing up Tina Turner's fiery, un-sum-up-able persona when he famously said, after joining her onstage in Birmingham, England, during the final concert of her 1985 British tour: "Standing up there next to her was the hottest place in the universe."
Here, on Tina Turner's 75th birthday (b. Nov. 26, 1939), LIFE.com presents a handful of previously unpublished photos taken in 1970 by Gjon Mili. The exact date of the shoot? Unknown. The location? Unknown. The show's set list? Unknown. The identity of the guy gazing back at Mili's camera in the last picture in this gallery? Unknown.
But one thing these pictures do manage to impart is confirmation that, when Tina Turner took the stage -- no matter where that stage was, and no matter how large or how small the crowd might be -- there was no simply no restraining her soulfulness, or her sex appeal.
Born Anna Mae Bullock, Turner grew up in rural Tennessee, the daughter of a church-deacon father and a part-Native American mom. Humble beginnings, indeed, for a women whose life and long career have seen their share of very low lows (a two-decade marriage to Ike Turner marked -- she maintains, and he denies -- by emotional and physical abuse) and tremendous highs: roughly 100 million records sold; multiple Grammys; Kennedy Center honors; iconic work on the big screen, e.g., the Acid Queen in Tommy; legions of fans; induction into the Rock and Roll Hall of Fame; and on and on.
Today, Tina Turner is a Swiss citizen -- she relinquished her U.S. citizenship in 2013 -- and lives, for the most part, in a small town just outside of Zurich. She married German music executive Erwin Bach in 2013, after a romantic relationship of more than a quarter-century. And at an age when most rockers are throttling it back a bit, her most recent major outing -- 2009's "50th Anniversary" tour -- played to more than a million people at more than 80 shows across North America and Europe and earned an estimated $130 million.
Liz Ronk, who edited this gallery, is the Photo Editor for LIFE.com. Follow her on Twitter at @LizabethRonk