On behalf of Sir Arthur Conan Doyle, there are some historical events about the beginnings of the LDS church that were known in his time.
An account of some of these actions is found at: http://www.utlm.org/onlinebooks/meadowscontents.htm
This account includes copies of documents of the period including the words of Joseph Smith, Brigham Young and testimony of those involved in the Mountains Meadows Massacre.
Here is a brief snoposis of what is covered:
It is not necessary to give the details of the blood atonement murder of William R. Parrish and his son Beason for “apostasy,”
at Springville, in 1856; of the murder of Rosmos Anderson by the leading priesthood of the Parowan “stake of Zion” in 1856,
because Philip Klingensmith, bishop of Cedar City, Utah, coveted the buxom Scandinavian stepdaughter of Anderson as his plural wife, and whom Anderson also wanted as his plural, and with whom, as alleged, he had committed adultery as the last and surest effort to secure a “recommend” to enter the “holy order of celestial marriage”; of the castration of Tom Lewis, at Manti, Utah, in 1856, because Bishop Warren Snow was lecherously ambitious to polygamously marry the girl with whom
Lewis was keeping company; of the inexpressibly cowardly murder of William Hatton at Fillmore, 1856, by a man who could
be named, and who was the agent of the “prophets, seers and revelators” at Salt Lake City, and whose handsome widow the
unspeakable “Prophet” Heber C. Kimball soon after added to his celestial harem; of the murder, by prophetic instructions, at
Farmington, during the spring of 1858, of four of the Aiken party, and while “Johnston’s” army at Ham’s Fork was preparing to enter Utah, and of the cowardly assassination of two others of the Aiken party by a present high churchman and his companion, who, under pretense of conducting them from Utah by the southern route to California, shot them in the back at a point some four or five miles south of Nephi, about 110 miles south of Salt Lake City; of the midnight murder, later on, of King, Brassfield and others who became obnoxious to the Mormon leaders. This is an abbreviated history of the Mountain Meadows massacre
- not of the entire diabolical results of the teaching of unquestioning obedience and blood atonement by the vicegerents of the Mormon god.
I am posting this in the interest of truth and full disclosure. I am not trying to malign the LDS church in any way.
For a nice list of books about the LDS church and its origins (both Mormon approved and nonapproved works) see: http://www.california.com/~rpcman/MO3.HTM