Danning was born in Wels, Upper Austria, Austria as Sybille Johanna Danninger. Danning was the love child of a German-Dutch-American father, who had to leave for the United States before Danning’s birth. Her Austrian mother raised her until she married a United States Army major, who relocated his new family to the United States. Danning led a nomadic early life on various Army bases in Sacramento, Maryland, and New Jersey.

Danning entered the realm of cinema when a German film director insisted she play the beautiful legendary figure, Lorelei, in his movie, Come, My Dear Little Bird. Her photograph posing on the infamous Lorelei Rock on the Rhine River in nothing but her long blonde tresses while luring sailors to their doom through song made her a sensation in the European press. A year after she was cast as yet another legendary beauty for the film The Long Swift Sword of Siegfried, in which her portrayal of Kriemhild was far more seductive than in director Fritz Lang’s 1924 treatment of the same source material. The next year, she had a role in one of Robert De Niro’s first films, Sam’s Song.

Now committed to acting, Danning trained for three years with noted Munich drama coach, Annemarie Hantschke. Yet the only roles she was offered were those exploiting her considerable beauty and sex appeal. Fifteen films later, Danning finally was given a more challenging roll as the bareback riding African farm girl in Whispering Death with Christopher Lee. She would go on to make five films with Lee in Europe over the span of a decade.

In 1972, she was in the cast of Bluebeard, along with Raquel Welch and Richard Burton, playing a high-class prostitute. The same year, she appeared in Eye of the Labyrinth, a giallo thriller. Also noteworthy were her films The Three Musketeers and The Four Musketeers, again acting with Raquel Welch; both films being produced by Ilya and Alexander Salkind. In 1977, she was praised for her role as a sadistic terrorist headed for Entebbe in the Best Foreign Film Oscar nominated Operation Thunderbolt with Klaus Kinski. As producer, Danning provided full financing out of Germany and distribution as well as cast her friend Klaus.

In 1978, Danning moved to Hollywood, California, to further her career in American films. She left all her friends and family in Europe behind, and pursued her career with no contract, no agent, and no idea what the future would bring. In 1980, Danning portrayed an extraterrestrial Amazon named Saint-Exmin in the science fiction film Battle Beyond the Stars. This performance earned her “The Golden Scroll Award of Merit” from the Academy of Science Fiction, Fantasy, and Horror Films.The cult films Jungle Warriors, Panther Squad, and S.A.S. San Salvador followed in quick succession.

Danning co-starred again with Christopher Lee in Howling II: Your Sister is a Werewolf, playing Stirba, an evil werewolf queen. She began to guest-star in many American television series, notably A Man Called Sloane, Vega$, Simon & Simon, Masquerade, The Fall Guy, and V (The TV series). In 1986, Danning was seen with the troubled rocker Wendy O. Williams in Reform School Girls, a campy “Women in Prison” film. After the sketch parody Amazon Women on the Moon, Danning founded her own production company, “Adventuress Productions, Inc.”, and produced L.A. Bounty, in which she starred and wrote the script.

In the vein of Elvira, Danning was the hostess of her own collection of 26 action-adventure films that bear the title Sybil Danning’s Adventure Video for the “USA Home Video” company.She appeared at the beginning, with campy one-liners, introduced the video, and returned at the end to wrap it up. In 1989, Danning re-teamed with the producers of Bluebeard, The Three Musketeers, The Four Musketeers, and The Prince and the Pauper to play a succubus in the television series Superboy.