The visionary achievements of Isabella (Isabel) Caroline Somerset (Lady Henry Somerset), like the temperance cause she led, have undeservedly faded into obscurity. By her contemporaries she was feted for her social activism, and at the time of her death in 1921, Isabel Somerset's vigorous reform efforts were acclaimed by humanitarian, political and social-reform organizations and the labour movement. She was internationally recognized for her contributions to the temperance cause, social reform and women's rights. The failure of her traumatic marriage to Lord Henry Charles Somerset after revelation of his homosexual affairs, and the ensuing child-custody battle and consequent ostracism by Society, combined with a profound religious experience, effected her metamorphosis from an aristocratic socialite into a temperance and social reform activist. Beginning with local temperance and philanthropic work, Isabel Somerset progressed to become president of the British Women's Temperance Association, which she gradually transformed from a single-issue organization into one committed to women's rights and a broad range of social initiatives; the BWTA became a potent pressure-group force in the politically influential, late-nineteenth-century temperance movement. Discouraged by the existing punitive, futile methods used to combat alcoholism, she founded a farm colony for female inebriates and employed a pioneering rehabilitation programme based upon therapeutic treatment and life-style changes. Through her close co-operation with American temperance icon Frances Willard, Isabel Somerset strengthened the bonds between the Anglo-American and international temperance and women's movements. Isabel Somerset's activism did not go unchallenged. In 1893 she successfully overcame the BWTA social-conservatives' attempts to unseat her, and thereafter expanded the membership to hitherto unprecedented levels. In 1897-8 her position on state-regulated prostitution in India created a controversy which reverberated beyond the Association to encompass its sister organizations and proved temporarily detrimental to Somerset's reputation and credibility. Isabel survived this disputation, retaining her presidency and succeeding Willard as president of the World's Woman's Christian Temperance Union following her death in 1898. Isabel Somerset was a devout Christian, compassionate humanitarian, temperance activist, committed social reformer and women's rights campaigner, a charismatic leader and eloquent orator. Her roles of reformer and women's advocate, as revealed anew in the pages of this biography, place her in the pantheon of notable Victorian female reformers.