HUMBOLDT, KARL WILHELM VON (1767-1835), German philologist and man of letters, the elder brother of Alexander von Humboldt, was born at Potsdam, on June 22, 1767. After studying at Berlin, Gottingen and Jena, in the last of which places he formed a close and lifelong friendship with Schiller, he married Fraulein von Dacherode, and in 1802 was appointed by the Prussian Government first resident and then minister pleni potentiary at Rome. While there he published a poem entitled Rom. His critical essay on Goethe's Hermann and Dorothea, published in 180o, had already placed him in the first rank of authorities on aesthetics, and, together with his family connections, had much to do with his appointment at Rome; while in the years 1795 and 1797 he had brought out translations of several of the odes of Pindar, which were held in high esteem. On quitting his post at Rome he was made councillor of State and minister of public instruction. He soon, however, retired to his estate at Tegel, near Berlin, but was recalled and sent as ambassador to Vienna in 1812. In 1813, as Prussian plenipotentiary at the congress of Prague, he was mainly instrumental in inducing Austria to unite with Prussia and Russia against France; in 1815 he was one of the signatories of the capitulation of Paris, and drafted the treaty between Prussia and Saxony, by which Prussian terri tory was largely increased. In 1816 he was at Frankfort, but was summoned to London in the midst of his work, and in 1818 had to attend the congress at Aix-la-Chapelle. The reactionary policy of the Prussian Government made him resign his office of privy councillor and give up political life in 1819; and from that time forward he devoted himself solely to literature and study.
In 1816 he had published a translation of the Agamemnon of Aeschylus, and in 1817 corrections and additions to Adelung's Mithridates, that famous collection of specimens of the various languages and dialects of the world. Among these additions that on the Basque language is the longest and most important, Basque having for some time specially attracted his attention. Wilhelm von Humboldt introduced Basque to the notice of European philologists, and made a scientific study of it possible. He visited the Basque country itself, the result of his visit being the valuable "Researches into the Early Inhabitants of Spain by the help of the Basque language" (Prii f ung der Untersuchungen caber die Urbewohner Hispaniens vermittelst der vaskischen Sprache, 1821) . Another work on what has sometimes been termed the metaphysics of language appeared from his pen in 1828, under the title of fiber den Dualis; but the great work of his life, on the ancient Kawi language of Java, was interrupted by his death on April 8, 1835. The imperfect fragment was edited by his brother and Dr. Buschmann in 1836, and contains the introduction on "The Heterogeneity of Language and its Influence on the Intellectual Development of Mankind," which was afterwards edited and defended against Steinthal's criticisms by Pott (2 vols., 1876). This essay, which has been called the textbook of the philosophy of speech, first clearly laid down that the character and structure of a language expresses the inner life and knowledge of its speakers, and that languages must differ from one another in the same way and to the same degree as those who use them. Other linguistic publications of Humboldt, which had appeared in the Transactions of the Berlin Academy, the Journal of the Royal Asiatic Society, or elsewhere, were republished by his brother in the seven volumes of Wilhelm von Humboldt's Gesammelte Werke (1841-52). These volumes also contain poems, essays on aesthetic subjects and other creations of his prolific mind.
Many volumes of Humboldt's interesting correspondence with his contemporaries have been published. The principal publications are the Correspondence with Schiller (i830; new ed. by Lutzmann, 1889) ; with Goethe (ed. Brateanek, 1876) ; with J. R. Forster (ed. Forster, 1889) ; with F. H. Jacobi (ed. Leitzmann, 1892) ; with A. W. Schlegel (ed. Leitzmann, 1908) ; with Karoline von Humboldt (ed. Sydow, 3 vols., 1906-09) ; and a selection of letters to various correspondents (ed. K. Sell, 1924) . A new edition of his Gesammelte Werke (1841-72, 7 vols.) was prepared for the Prussian Academy (15 vols., 1903-18) . Of the many works dealing with W. von Humboldt see B. Gerhardt, W. v. Humboldt als Staatsmann (1896-99, 2 vols.) ; O. Harnack, W. v. Humboldt (1913) ; Leitzmann, W. v. Humboldt (1919) .