Theodoric of Niem

Dietrich of Nieheim (Niem or Nyem) (c. 1345 – 22 March 1418), medieval historian, was born at Nieheim, a small town subject to the see of Paderborn.

He became a notary of the papal court of the rota at Avignon, and in 1376 went with the Curia to Rome. Urban VI here took particular notice of him, made him an abbreviator to the papal chancery, and in 1383 took him with him in his visit to Charles III of Naples at Naples, an expedition which led to many unpleasant adventures, from which he escaped in 1385 by leaving the Curia. In 1387 he is again found among the abbreviators, and in 1395 Pope Boniface IX appointed him to the Prince-Bishopric of Verden. His attempt to take possession of the see, however, met with successful opposition; and he had to resume his work in the chancery, where his name again appears in 1403.

In the meantime he had helped to found a German hospice in Rome, which survives as the Institute dell' Anima, and had begun to write a chronicle, of which only fragments are extant. His chief importance, however, lies in the part he took in the controversies arising out of the Great Schism. He accompanied Gregory XII to Lucca in May 1408, and, having in vain tried to make the pope listen to counsels of moderation, he joined the Roman and Avignonese cardinals at Pisa. He adhered to the pope elected by the council of Pisa (Alexander V) and to his successor, Antipope Pope John XXIII resuming his place at the Curia. In view of the increasing confusion in the Church, however, he became one of the most ardent advocates of the appeal to a general council. He was present at the council of Constance as adviser to the German "nation." He died at Maastricht on 22 March 1418.

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