The Lord has, I believe, blessed me greatly in having access to important documents relating to post-1890 polygamy. … I have found important MSS [manuscripts] which show the role of [LDS First Presidency counselor] George Q. Cannon in advocating post-1890 polygamy, which show the manipulations and strategies involved in the [Reed] Smoot Case and resultant resignations of [LDS Apostles Matthais F.] Cowley and [ John W.] Taylor, and which have highlighted other aspects of post-1890 polygamy.
During 1971, I verified that [LDS Apostles] Heber J. Grant and Francis M. Lyman (traditionally considered as implacable foes of post-1890 polygamy) had each performed a few plural marriages after 1890, and that Heber J. Grant unsuccessfully tried to marry a plural wife after 1890. I also found other tid-bits of importance to this subject during 1971. After I became a member of the HDC [Historical Department of the LDS Church] a few weeks ago, my ability to pick up information increased. Being a staff member[,] I could wander through the stacks of MSS [manuscripts] without supervision. This gave me the opportunity to find what I could by snooping around. In this way[,] I located the sealing records of Patriarch Alexander F. Macdonald of Juarez [Mexico] Stake (1900–1093); the record of some plural marriages performed by Apostle Marriner W. Merrill between 1894–1903, and a record called Temple Book B, which recorded over 300 sealings [i.e., marriages] performed outside the temple from 1891–1903 (at least 9 of which were polygamous marriages—including that of [Apostle] George Teasdale performed [in 1897] by Apostle Anthon H. Lund). … … I feel [that] the Lord has allowed me to find as much information as He has for a purpose. I believe that this purpose is for me to write a detailed and comprehensive history of this era [of post-1890 Manifesto polygamy]—why I do not know. But I will never attempt to write such a history unless I have researched those additional sources I regard as absolutely essential to understanding the full story of this period of quiet and secret continuation of polygamy.
[From the diaries and memoirs of D. Michael Quinn, in 'On Writing Mormon History, 1972-95,' edited by Joseph Geisner, Signature Books, 2020]