Henry Frederick Amedroz (1854–1917), one of the founding Trustees of the Gibb Memorial Trust, was the editor of the collection of eleventh-century Arabic historical sources published posthumously in 1920–21 as The Eclipse of the ‘Abbasid Caliphate. This collection remains the definitive edition of these important texts for the history of Iraq and Iran in the ninth, tenth and eleventh centuries. D. S. Margoliouth's (1858–1940) translations, published with Amedroz's edition, are likewise still widely used. The Eclipse marked the culmination of more than thirty years of scholarly work by Amedroz on the manuscripts of Arabic narrative histories composed by the scribal elites of the tenth- and eleventh-century ‘Abbasid and Buyid empires, as well as on Arabic numismatics and on other medieval Arabic texts. This was a project that Amedroz had taken up aged around thirty, alongside his professional work as a lawyer in London. In his studies, Amedroz must have felt the resonances between the position of the ‘Abbasid and Buyid scribes and his own family's situation, in the British Empire at its Victorian and Edwardian height.

Amedroz's father, with whom he shared his forenames, was of Huguenot ancestry and served as a secretary to the First Naval Lord. His mother, Magdelene Thornton (d. 1890), was from a wealthy Grenadian plantation-owning family; Magdelene's great-grandmother, Jeanette, had been a freed slave. The junior Henry Frederick Amedroz was born on 8 November 1854; according to Margoliouth's obituary in the Journal of the Royal Asiatic Society, he went to Winchester School on a scholarship in 1866, after which he initially sought to join the ‘Turkish Dragomans’ (by which Margoliouth may mean diplomatic interpreters in the Foreign Office). However, having passed the initial examination in 1877, he was rejected on medical grounds. He then attended University College, London, and was called to the Bar (Inner Temple) in January 1882, becoming one of the ‘Bar Reporters in the Chancery Courts’.

According to Margoliouth, it was after Amedroz joined the Bar that he took up the study of Arabic. The study of classical Arabic manuscripts and coins became a lifelong commitment, taking Amedroz to libraries in Britain and elsewhere.