Convert and controversialist, b. at Holtorf in Hanover, 7 February, 1590 (according to other sources in 1584 or 1589, at Wolpe in Brunswick); d. at Erfurt, 10 March, 1657. He came from a poor Protestant family, obtained his early education at Verden and Goslar, and from 1607 studied philosophy and medicine at the University of Helmstedt, where, on account of his poverty, he was the famulus of Cornelius Martini, professor of philosophy. Having become master of philosophy in 1612, his inclinations then led him to study Protestant theology. Contentions among the professors at Helmstedt made further stay there unpleasant, and when two students of noble family went in 1616 to the University of Jena, he accompanied them as preceptor. Later he became instructor of the young princes of Saxe-Weimar among whom was the subsequently famous Bernhard of Saxe-Weimar. The inability of the Protestant theologians to agree upon vital questions caused him first to doubt and then to renounce Protestantism. He went to Cologne in 1622, and entered the House of Proselytes founded by the Brotherhood of the Holy Cross; in the same year he accepted the Catholic Faith and, after due preparation, was ordained priest. Chosen director of the House of Proselytes, and in 1627 provost of the nunnery of the Cistercians at Althaldensleben near Magdeburg, two years later he became abbot of the monastery of the Premonstratensians, from which he was expelled after the battle of Breitenfeld in 1631. He fled to Hildesheim where he became canon of the church of the Holy Cross, thence to Holland where he came into close relation with Gerhard Johann Vossius. In 1645 Nihus was called to Munster by the papal nuncio, Fabio Chigi (later Alexander VII), then in Munster attending the Westphalian Peace Congress. A few years later he was induced to come to Mayence by Johann Philip von Schonborn, Archbishop of Mayence, at whose request he went to Ingolstadt in 1654 to obtain information regarding the Welt-Priester-Institut of Bartholomew Holzhauser, and to report to the archbishop. Schonborn, in 1655, appointed him his suffragan bishop for Saxony and Thuringia, with residence in Erfurt, where he died.

After his conversion Nihus had sent to the Helmstedt professors, Calixtus and Hornejus, a letter in which he presented his reasons for embracing Catholicism; his chief motive was that the Church needs a living, supreme judge to explain the Bible and to settle disputes and difficulties. Calixtus attacked him first in his lectures and later in his writings, whence originated a bitter controversy between Nihus and the Helmstedt professors. The most important of Nihus' numerous writings are: (1) "Ars nova, dicto S. Scripturae unico lucrandi e Pontificiis plurimos in partes Lutheranorum, detecta non nihil et suggesta Theologis Helmstetensibus, Georgio Calixto praesertim et Conrado Hornejo" (Hildesheim, 1633); (2) "Apologeticus pro arte nova contra Andabatam Helmstetensem" (Cologne, 1640), in answer to the response of Calixtus to the first pamphlet: "Digressio de arte nova contra Nihusium"; (3) "Hypodigma, quo diluuntur nonnulla contra Catholicos disputata in Cornelii Martini tractatu de analysi logica" (Cologne, 1648). Assisted by his friend Leo Allatius (q.v.) he devoted considerable time to researches pertaining to the "Communion" and the "Missa praesanctificatorum" of the Greeks, and also took charge of the editing and publishing of several works of Allatius, some of which - as the "De Ecclesiae occidentalis et orientalis perpetua consensione" (Cologne, 1648) and "Symmicta" (Cologne, 1653) - he provided with valuable additions and footnotes.

Koch, Die Erfurter Weihbischofe in Zeitschrift fur thuringische Gesch., VI (Jena, 1865), 104-9; RASS, Die Convertiten seit der Reformation, V (Freiburg im Br., 1867), 97-103; WESTERMAYER in Kirchenlex, s. v.; IDEM in Allg. deutsche Biog., XXIII, 699 sq.

FRIEDRICH LAUCHERT