Ina Fagan was born October 15, 1893, in Washington, D.C. After the death of her father, Claire began doing imitations of fellow boarders in the boarding house where she and her mother, Cora, and brother, Allen,[2] were forced to live.

[3] In 1906, she gave a recitation as the grand finale of a program presented by Miss Cora B. Shreve's pupils in Washington, D.C. She was identified in a newspaper article as Ina Claire Fagan.

She later starred on Broadway in plays by some of the leading comic dramatists of the 1920s, 1930s, and 1940s, including the roles of Jerry Lamarr in Avery Hopwood's The Gold Diggers (1919), Mrs. Cheyney in Frederick Lonsdale's The Last of Mrs. Cheyney (1925), Lady George Grayston in W. Somerset Maugham's Our Betters (1928), and Enid Fuller in George Kelly's Fatal Weakness.

[7] Claire later became identified with the high comedies of S. N. Behrman, and created the female leads in three of his plays: Biography (1934), End of Summer (1936), and The Talley Method (1941).

[11] She is best remembered today for her role as the Grand Duchess Swana in the romantic comedy Ninotchka (1939), directed by Ernst Lubitsch and starring Greta Garbo.