Prussian Historical Institute in Rome

Roman Historical Institutes are collegiate bodies established at Rome, for the purpose of historical research, mostly in the Vatican archives. These have been set both by ecclesiastical authority, and by national governments.

In the fifteenth and sixteenth centuries the awakening critical investigation of the past led some scholars to resort to the treasures of the papal archives. The most far-reaching and efficient use of the archives for historical purposes began with Cæsar Baronius. Through his work, and in the several continuations of it by others, the world first learned of the wealth of historical documents contained in the Roman archives, and especially in the archives of the Vatican. The extensive Bullaria, or compilations of papal decrees, general and particular (see Bulls and Briefs), are drawn in part from the archives of the recipients, have only reached their imposing array of volumes because the Vatican furnished abundant material.

In the seventeenth and eighteenth centuries, ecclesiastical historians and the writers of the numerous monographs concerning local churches, monasteries, ecclesiastical institutions, etc. were aided by the officials of the archives, themselves often scholarly investigators. In this respect the papal archivist Augustin Theiner (1804–74) accomplished far-reaching work when he published, in many folio volumes, a multitude of documents relative to the ecclesiastical and civil history of Northern, Eastern, and Southern Europe, also a documentary treatise in three folio volumes on the temporal dominion of the pope and its administration. In the same period, i.e. from about 1850 to 1875, several other investigators, chiefly German and Austrian, in one way or another secured admittance to the papal archives. These events and other influences increased the desire of all scholars for the opening of this valuable repository of important historical documents. Although under Pope Pius IX it became somewhat easier to obtain a permit for private research, the political conditions of his reign worked against a general opening of the Vatican Archives.

"We have nothing to fear from the publication of documents", exclaimed Pope Leo XIII, when on 20 June 1879, he appointed the ecclesiastical historian, Joseph Hergenröther, "Cardinal Archivist of the Holy Roman Church" (Palmieri, "Introite ed Esiti di Papa Niccolò III", Rome, pp. xiv, xv; Friedensburg, "Das kgl. Preussische Historische Institut in Rom", Berlin, 1903, passim). He opened to students the archives of the Vatican, more especially what are known as the secret archives, despite strong opposition from several quarters.

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