John was born in Zürich, Switzerland, the son of the Rev. Heinrich and Rosalie (Mueller) Nuelsen. Heinrich, born in Nörten, Hanover, became an American citizen and was ordained into the Methodist Episcopal ministry. He spent time in Germany as a missionary, and later was sent to Switzerland to help establish Methodism there. He served churches in Europe for thirty-eight years. The family was originally from Holland. John was baptized by Bishop Calvin Kingsley.
John married Luella Elizabeth Stroeter (daughter of Ernst Ferdinand & Caroline Ströter) on 8 September 1896. They had the following children: Albert E., Henry E., John Louis, Jr., and Marie L.
In 1890, the Rev. Nuelsen was appointed a Professor at St. Paul's College in St. Paul Park, Minnesota, serving until 1892. During 1892-93 he completed his Master's degree. In 1894 he was appointed a Professor at his alma mater, Central Wesleyan College, serving until 1899.
In 1899 the Nast Theological Professorship in Exegetical Theology was established at German Wallace College, Berea, Ohio with a gift of $20,000 given by Franzeska Wilhelmina "Fanny" Nast Gamble, daughter of the Rev. William Nast (the first President of German-Wallace) and wife of William Gamble (son of Procter and Gamble co-founder James Gamble). The Rev. Dr. John L. Nuelsen was called to this new chair. After three years this department was expanded into the Nast Theological Seminary, which served well in the training of ministers and workers in Christian vocations from 1902 until 1933, especially those of German descent. Dr. Nuelsen served his Professorship until 1908.
He was elected a delegate to the M.E. General Conferences in 1904 and 1908. He also attended the Ecumenical Conferences of 1901 and 1911.
Episcopal ministry
Bishop Nuelsen was elected to the episcopacy by the General Conference of 1908. His election came primarily as a result of a rather strong insistence upon the part of the German constituency of the M.E. Church that they should be represented in the Board of Bishops. This election was thus an early manifestation of the conviction, registered often in more recent years, that minority groups in the Church should furnish a part of the Episcopacy.
Once elected, however, Bishop Nuelsen was assigned, not to preside over German Conferences, but to a regular Area of the Church in the United States. He was assigned to the Omahaepiscopal area (Nebraska) until 1912. Then he was assigned all the work in Europe, with his residence in Zürich. He was associated with the work of the Church in Europe for the rest of his active episcopacy (until 1940). At first his Episcopal Area covered all annual conferences in Switzerland, Germany, Scandinavia, Russia, France, Spain, Italy and Austro-Hungary. In 1920 the European work was divided into three Episcopal Areas: the Stockholm Area, the Paris Area, and the Zürich Area (to which Bishop Nuelsen was assigned).
Bishop Nuelsen is remembered by fellow-Methodist Bishop Roy H. Short as:
an impressive man. He looked the scholar that he was. His library, which can still be seen in the Methodist Publishing House in Zurich, bears silent testimony to the wide range of his interests and the eagerness of his mind for acquiring knowledge. He wrote constantly and was the author of a number of books and of a multitude of articles. He was an indefatigable traveler, and much of his study and writing was done on the road.
Wartime
World War I was especially difficult for Bishop Nuelsen. He loved the German Methodists and the German People, and hastened to defend them in the early years of the war. When the United States entered the war, however, matters became further complicated for him. The charge of being "pro-German" was a serious one at that time in the opinion of many Americans during the highly emotional days of 1917–18. Nuelsen was attacked in some American church papers. Even some of his Episcopal brethren were not too understanding of the situation in which he found himself. During the last period of the war he was in fact forbidden to travel, being immobilized in Switzerland for long months. A further complication was the fact that the conferences under his care were divided between nations on the side of Germany and nations on the side of the Allies.
Selected writings
Jugend, Kirche und Statt, 1896.
Die Bedeutung Des Evangeliums Johannes, 1903.
Das Leben Jesu in Wortlaut der vier Evangelien., 1904
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