Born in Vienna, Austria to artist Emil Jakob Schindler and his wife Anna von Bergen, in a privileged environment. Her father's friends included Gustav Klimt, to whom she gave her "first kiss". As a young woman she had had a series of flirtations, including Klimt, director Max Burckhard and composer Alexander Zemlinsky. In 1902 she married Gustav Mahler, even though the composer was twenty years older than her. The terms of this marriage were that Alma would forego her own artistic interests in painting and music. Resenting this, Alma began an affair with the Bauhaus architect Walter Gropius: Mahler had a single consultation with Dr. Sigmund Freud as to the causes for his dissatisfied relationship. When Mahler died in 1911, Alma married Gropius.
The marriage was tumultuous. For two years, Alma had an affair with artist Oskar Kokoschka, who painted his Bride of the Wind to represent their love. Fearful of the passion he evoked in her, Alma left Kokoschka for novelist Franz Werfel, and even became pregnant - she thought by him - while still married to Gropius. She divorced Gropius and married Werfel in 1929, but the child, Martin, was born prematurely and died aged ten months.
Alma and Gropius's daughter, Manon, died of polio in 1935. Composer Alban Berg wrote his Violin Concerto in memory of her.
In 1938 Alma and Werfel were forced to flee Austria for France to escape the Anschluss. With the German invasion and occupation of France during World War II, and the deportation of Jews to the Nazis death camps, she and her husband had to flee France. With the assistance of the American journalist Varian Fry in Marseille, they escaped the Nazi regime via a riveting journey across the Pyrenees to Spain and from there to Portugal where they sailed to New York City. Eventually they settled in Los Angeles, where Werfel achieved a measure of success when his Song of Bernadette was made into a 1943 film starring Jennifer Jones. After Werfel's death in 1945, Alma moved back to New York where she was a major cultural figure until her death in 1964.
Her much-married state is made sport of in Tom Lehrer's song Alma. Her life is recounted in the 2001 Bruce Beresford film Bride of the Wind.