She was educated at Queen"s College, London and Lady Margaret Hall, Oxford where she graduated with a Master of Arts.
In 1945 she became known as Lady Mander. In 1929 she was employed as Secretary to the Liberal Member of Parliament Edgar Granville. In July 1930 she was selected as Liberal prospective parliamentary candidate for the Reading Division of Berkshire for the General Election that was to occur in 1931.
By the time the General Election came, a National Government had been formed and the Reading Liberals did not contest the constituency.
Although she remained interested in politics, she did not attempt to stand again for public office and instead concentrated on her writing. She was a noted biographer with a special interest in the writers and artists of the Romantic period and an early connoisseur of the Pre-Raphaelite movement.
Her biographical subjects included Mary Shelley (1938), Claire Clairmont (1939), Edward John Trelawny (1950), William Godwin (1953), Dante Gabriel Rossetti (1965), Ivy Compton-Burnett (1971) and Elizabeth Barrett Browning (1980). She was influential in the overdue reassessment of the artists and writers of the Victorian period.
She lectured frequently in the United States of America.