He acted for some time as military governor of Siena, represented Spain diplomatically at the Council of Trent, and in 1547 was nominated special plenipotentiary at Rome, where he remained till 1554.
The remaining years of his life, which were spent at Granada, he devoted to the study of Arabic (which he had learned at home when growing up[4]), to poetry, and to his history of the Moorish insurrection of 1568–1570.
In some passages the author deliberately imitates Sallust and Tacitus; his style is, on the whole, vivid and trenchant, his information is exact, and in critical insight he is not inferior to Juan de Mariana.
[2] The attribution to Mendoza of Lazarillo de Tormes is disputed, but documents recently discovered by the Spanish paleographer Mercedes Agulló reinforce the hypothesis.
Mendoza is also believed to be the author of the letters to Feliciano de Silva and to Captain Salazar, published by Antonio Paz y Melia in Sales Espanolas (Madrid, 1900).