The latter part of the history of Mendoza’s life is not uniformly related by his biographers. According to some he retired to the country, devoted himself to poetry and philosophy, and appeared very seldom at the court of Philip II. Others assert that, though he no longer retained his former influence, he continued a member of the council of state under Philip II. and was present with that monarch at the great battle of St. Quintin, fought in the year 1557. This much is certain, that he was soon after engaged in an adventure at the court, which, for a man of his age and knowledge of the world, was of a very singular nature. An altercation arose in the palace between him and a courtier, who, according to Mendoza’s own declaration, was his rival in the affections of a lady. This man, whose name is not mentioned, in a fit of violent exasperation, drew a dagger; upon which Mendoza seized him, and threw him from a balcony into the street. What afterwards became of his antagonist is not recorded; but the transaction was the subject of serious observation, and the grave Philip regarded it as a high offence against the dignity of his person and his court. He was, however, content to inflict a moderate punishment, and merely condemned Mendoza to a short imprisonment. The old statesman occupied the period of his imprisonment in the ancient Spanish style, namely, in composing lamentations on the unkindness of his mistress:[171] and these romantic effusions do not appear to have been considered by his contemporaries as absurd and ridiculous at his time of life. But the sorrows expressed in his amatory ditties did not drive the venerable lover to despair; for when he was soon after set at liberty, though still exiled from court, he observed with the eye of a politician the insurrection of the Moriscoes, or converted Arabs of Granada; and when the insurrection broke out into a formal war, he noted down all the remarkable events, and afterwards detailed them in an historical work, which has obtained for him the name of the Spanish Sallust. He profited of this opportunity to collect a great number of Arabic manuscripts. Observations on the works of Aristotle, a translation of the Mechanics of that philosopher, and some political treatises, were, it appears, the last of his literary labours. He was thus actively and usefully employed until his death, which happened when he was upwards of seventy, at Valladolid, in the year 1575. He bequeathed his collection of books and manuscripts to the king, and it still forms one of the most valuable portions of the library of the Escurial.[172]