D. Michael Quinn writes on the history of post-manifesto polygamy.
D. Michael Quinn, "LDS Church Authority and New Plural Marriages, 1890-1904," Dialogue: A Journal of Mormon Thought 18, no. 1 (Spring 1985): 9–105
Were new plural marriages actually performed after the 1890 Manifesto? In 1907, the First Presidency announced, "When all the circumstances are weighed, the wonder is, not that there have been sporadic cases of plural marriage, but that such cases have been so few." 13 In 1922, Church Historian Joseph Fielding Smith wrote that "some plural marriages had been entered into contrary to the announcement of President Woodruff, and also a statement made by President Lorenzo Snow." Assistant Church Historian B. H. Roberts wrote in the Church's centennial history that "the injunction of said Manifesto had not been strictly adhered to even by some high officials of the Church of Latter-day Saints and people misled by them."
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This was the Abrahamic ram in the thicket of which the First Presidency secretary spoke; but like the decision of the First Presidency in June 1890 to end polygamy, it was impossible to impress non-Mormons with the unannounced sacrifice of something that the Presidency had always denied they were doing anyway. The hierarchy had taken a series of unpremeditated steps that external pressures allowed to end in only one outcome: the announcement of the resignations of Taylor and Cowley for being out of harmony regarding post-Manifesto polygamy and the appointment of their successors in the Quorum of the Twelve Apostles on 9 April 1906. When Anthony W. Ivins had learned about the resignations signed in October 1905 he wrote his cousin Heber J. Grant, "It might be all right if it were going to deceive anyone except ourselves. We will be the only ones fooled." The published statements about post-Manifesto polygamy that began this paper demonstrate the general truth of this assessment by a man who was in a better position than most to understand the relationship of Church authority and new plural marriages from 1890 to 1904.
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Moreover, the saga of new plural marriages among the Mormons continued after 1904. It does not take a very close reading of the First Presidency letter of October 1904 to realize that it rescinded only authorizations given by Presidents Woodruff and Snow to seal marriages out of the temple and did not mention any similar authorizations given by Joseph F. Smith. And so the ambiguity persisted, enough to allow certain General Authorities in the next three years to make fewer than ten exceptions to what was now almost a universal ban on new polygamy. Still, within a few years after 1904, men like Judson Tolman, Samuel Eastman, John W. Woolley, and others would perform and enter into scores of new plural marriages without claiming authorization from the Church president. But that story remains to be told.