INTRODUCTION
A person whose name finds mention in thebooks about Byron, and to some extent in thoseabout Shelley, was John William Polidori, M.D.; hewas Lord Byron's travelling physician in 1816, whenhis Lordship quitted England soon after the separationfrom his wife. I, who now act as Editor of hisDiary, am a nephew of his, born after his death.Dr. Polidori figures not very advantageously in thebooks concerning Byron and Shelley. He is exhibitedas overweening and petulant, too fond of puttinghimself forward face to face with those two heroes ofour poetical literature, and too touchy when either ofthem declined to take him at his own estimation. Iwill allow that this judgment of Polidori is, so far as itgoes, substantially just; and that some of the recordedanecdotes of him prove him deficient in self-knowledge,lacking prudence and reserve, and ignoring the distinctionbetween a dignified and a quarrelsomeattitude of mind. He was, in fact, extremely youngwhen he went abroad in April 1816 with Byron, towhom he had been recommended by Sir HenryHalford; he was then only twenty years of age (bornon September 7, 1795), Byron being twenty-eight,and Shelley twenty-three. The recommendationgiven to so very young a man is a little surprising.It would be a mistake, however, to suppose thatPolidori was without some solid attainments, andsome considerable share of talent. He was the sonof Gaetano Polidori, a Tuscan man of letters who,after being secretary to the celebrated dramatistAlfieri, had settled in London as a teacher of Italian,and of his English