Soma was born in Manhattan, New York, the daughter of immigrant parents from the small town of Ispra in northern Italy.
Her father Antonio Angelo "Tony" Soma was an entrepreneur; her mother Angelica (née Fantoni, 1891–1933), an aspiring singer and actress.
Her father ran the famed Tony's Wife restaurant in Manhattan, a popular celebrity dining spot for figures such as Dorothy Parker.
[5][6][7][8] In 1949, she participated in a later famous Life magazine photo layout, in which she posed with other up-and-coming actresses, Marilyn Monroe, Lois Maxwell, Cathy Downs, Suzanne Dalbert, Laurette Luez and Jane Nigh.
The director John Huston saw Soma's photo and began pursuing her, although he was married to actress Evelyn Keyes at the time.
Around this time, Soma had an affair with John Julius Norwich, and gave birth to their daughter Allegra Huston (b.