NEXT, the matter of setting aside King Richard, and choosing Henry, duke of Lancaster, in his stead, and how it was to be done and for what reason, was judicially commissioned to be debated on by certain doctors, bishops and others, of whom I, who am now noting down these things, was one. And it was found by us that perjuries, sacrileges, unnatural crimes, oppression of his subjects, reduction of his people to slavery, cowardice and weakness of rule—with all which crimes King Richard was known to be tainted—were cause enough for setting him aside in accordance with the chapter: “Ad apostolicae dignitatis,” under the title: “De re judicata,” in the Sextus; and although he was ready himself to yield up the crown, yet it was determined, for the aforesaid reasons, that he should be deposed by the authority of the clergy and people, for which purpose they were summoned.
On St. Matthew’s day (21st September), just two years after the beheading of the earl of Arundel, I, the writer of this history, was in the Tower, wherein King Richard was a prisoner, and was present at his dinner, and marked his mood and bearing, having been taken thither for that very purpose by Sir William Beauchamp. And there and then the king discoursed sorrowfully in these words: “My God! a wonderful land is this, and a fickle; which hath exiled, slain, destroyed, or ruined so many kings, rulers and great men, and is ever filled and toileth with strife and variance and envy”; and then he recounted the histories and names of sufferers from the earliest habitation of the kingdom. Perceiving then the trouble of his mind, and how none of his own men, nor such as were wont to serve him, but strangers who were but spies upon him, were appointed to his service, and musing upon his ancient and wonted glory and on the fickle fortune of the world, I departed thence, much moved at heart . . .
Adam of Usk, The Deposition and Death of Richard II from Chronicon Adae de Usk, London, J. Murray, 1876, edited and translated by Edward Maunde Thompson for the Royal Society of Literature.
Adam of Usk entry from the Dictionary of National Biography, 1885-1900 (Link)