JOHN ARMSTRONG was a leading authority on the history of later medieval Burgundy. The characteristics of his work were a penetrating power of observation and a close attention to detail. In a series of seminal articles he offered authoritative surveys of ducal policy to the nobility, the politics of the language question in the Low Countries and cultural relations between Burgundy and England. In a lengthy article in French he examined the matrimonial relations between the Valois dukes and the royal house of France.
Armstrong's knowledge of the sources for the Burgundian domains was formidable. He was particularly at home in the archives of northern and eastern France. It was in the course of a visit to the Bibliotheque Municipale at Lille in the 1930s that he stumbled across a source which he realised was of great importance to English history. This was the sole surviving text of Dominic Mancini's Usurpation of Richard III. Mancini's was an eye-witness account of events in England in 1483, written for an Italian patron, Angelo Cato. Not only did the account offer a wealth of detail not available elsewhere; it was especially informative of the reactions of contemporaries, notably in regard to the disappearance of the princes. Armstrong's discovery was therefore one of the highest importance. His edition and translation of the text, a model of precise scholarship, was published by Oxford University Press in 1936.
Armstrong's interest in the politics of Yorkist England, once awakened, stayed with him for life. In 1948 he published an important article on the inauguration rituals of the Yorkist kings, and later he wrote on aspects of the history of the Wars of the Roses. As for many of his contemporaries, his chosen vehicle of expression was the learned article. By nature a miniaturist, he used the medium to perfection. By examining a small episode, he would hint at the larger synthesis to which it held the key. Characteristically, every phrase, every sentence, that he wrote was loaded with meaning.
His style as a teacher was inimitable. Lectures, which in his later years, as a result of gout, were delivered sitting down, were characterised again by his attention to detail. Invariably he would range widely over his theme, building up his picture piece by piece and episode by episode. In tutorials his comments, though sparingly given and often seemingly oblique, were penetrating and acute. He was a master at exploring side-issues, or the role of minor characters in a drama, to shed light on a larger issue or theme.
Armstrong's entire academic career was spent at Hertford, the Oxford college at which he had been an undergraduate. For the 30 and more years of his Fellowship he was one of the college's most colourful personalities. He was someone instantly recognisable - a large well-built man, with a pronounced stoop, invariably dressed in a grey or navy-blue pin-striped suit.
His views on college issues were always strong, and on occasion eccentric. If he did not like someone, he would not hesitate to indicate as much. It was not unknown for him at dinner, if he found the company uncongenial, to descend from the High Table and eat with the undergraduates. He was engagingly contemptuous of college rules: often in disregard of convention he would walk straight across the lawn of the Old Quad to the Common Room. He was at all times intolerant of cant or hypocrisy.
Armstrong was a man of catholic interests and taste. He enjoyed travelling in Europe, particularly in France, and had an extensive knowledge of medieval art and antiquities.
Outside medieval history, his main interests lay in the world of botany. He was a keen collector of rare plants, and he had a long association with the university botanical garden at Oxford.
Armstrong was a warm and civilised man with a kindly smile and an irreverent wit. He maintained a beautiful home at Boars Hill, outside Oxford, with his devoted wife Elizabeth, herself a distinguished scholar and an Emeritus Fellow of Somerville.