[1] She was the younger daughter of the Spanish diplomat and writer Salvador de Madariaga and the Scottish economic historian Constance Helen Margaret (née Archibald).
[5] As a consequence of her father's career,[4] De Madariaga lived in Geneva during her early years because he was working for the League of Nations before he moved to Paris to be the United States ambassador for the Spanish republic.
[3][4] At the age of 18,[6] De Madariaga went to London and was the first woman undergraduate student to enroll on a Russian language and literature degree at the School of Slavonic and East European Studies (SSESS).
[1] De Madariaga was secretary on the editorial board of The Slavonic and East European Review from 1951 to 1964, a post that allowed her to do part-time research,[1] and earned a Doctor of Philosophy for a two-volume dissertation,[3] on Anglo-Russian relations during the American Revolutionary War.
[4][6] It was published as Britain, Russia and the Armed Neutrality of 1780: Sir James Harris’s Mission to St Petersburg during the American Revolution in 1962 and provided a greater insight into Russian court politics.
[8] After a series of operations, which did not bring about an improvement in her condition,[8] De Madariaga died of bronchopneumonia at the Royal Free Hospital, London Borough of Camden on 16 June 2014.
"[4] He noted recognition in the professional field led her to become more kind and more interested in individuals and assisted fellow specialists: "The determination that had enabled her eventually to become a full-time academic also sustained her intellectual curiosity long into old age.
"[4] De Madariaga was credited for transforming the study of Russia in the 18th century and had changed perception on how Catherine the Great and Ivan the Terrible were viewed by scholars and Russian and Western historians.
[2][3][4] Before her works were published, little attention had been focused on Catherine's achievements on wanting Russia to "take her rightful place as a civilised member of the family of European great powers" while under various constraints during her reign,[3][4] and more on her private life.