So little is taught by the church about its own hand in violence.
1) Ohio: JS wasn't just tarred and feathered b/c of religious reasons. There are reports that the mob called for the physician to castrate him, and that he'd been fooling around with the 16-year old girl of the home, who 10-years later became one of his plural wives.
2) Missouri: JS raised an army and marched it from OH to MO on the Zion's Camp March. This was seen as a threat to the Missourians.
3) Missouri: The Danite Malitia was 85 Mormon men who signed the pledge (more joined later) in MO -- it was the precursor to the Nauvoo Legion. There was disaffection among former Mormons, as there was a purging of excommunications in 1838 (when there was both Kirtland and Far West) of key people including BOM witnesses and church leaders (Oliver Cowdery, many of the Whitmers, etc.) (they spoke against Joseph's affair with Fanny Alger in Kirtland, etc.).
Many of these former Mormons people owned lands in northwest MO and the local Mormons there did not take well to them. Sydney Rigdon gave a July 4, 1838 speech known as the "Salt Sermon," in which he threatened the ExMos with violence (Sydney used the word "exterminate) saying they were as the salt of the earth and had lost their favor.
The Danite Malita posted notices on ExMormons' homes threatening them with violence if they would not leave, and homes, barns and shops were burned by the Mormon Danite Malitia (near Millport, Gallitan, Grindstone Forks) and there were reports of cattle that were rustled. The Danite Malitia even burned the county seat building in Gallitan county, where many ExMormons had settled, and where there were the most agitators against the LDS church. This was known as the Missouri-Mormon War. This was the defense of property and liberty that Gov Boggs was responding to, and why JS, SR, LW were put in Liberty Jail. The Danite Malitia attacked the MO State Malitia at Crooked Creek. The one-sided history I was taught of LDS being victims, is not a proper account of history.
Sadly, months later Gov Boggs replicated Sydney's "extermination" word that Sydney Rigdon had used
4) Nauvoo: Joseph came out of Liberty Jail, I believe with a resolve to not be abused again, or so he felt (when in fact it was a two-sided issue in violence). So, under the generous Nauvoo City Charter from Springfield, the Mormons were allowed to build a legion -- which Joseph did and it became the second largest standing army outside of the US army. Certainly, neighboring towns of Warsaw, Quincey, Carthage -- were concerned. Joseph paraded the legion, they drilled, he had gold epilets on his uniform, etc. As a child I was taught the Nauvoo Legion was a thing of dignity and self-preservation. I now see that Joseph did not turn the other cheek.
In summary on IL violence, I think had the Mormons not raised an army, had they not gotten involved with secretive polygamy, and had Joseph not been preaching secretly in the Council of 50 (word got out) about setting up a theocratic kingdom of God on earth to subdue all other governments -- they would not have had the issues in IL they did. Neighboring cities weren't as concerned about a new religion (those were actually pretty common for the time), but certainly a standing army of that size, reports of secretive polygamy, and reports that Joseph had been appointed King of the Earth and Heaven (Council of 50), were of concern and you can read those in the Warsaw Signal, etc. No doubt Joseph made enemies too by lifting the Masonic Temple Rite ceremony.
Joseph felt the abrasion and the very nature of the Council of 50 was to find land outside of the US where they could practice their religion (polygamy, Joseph as King). The Council of 50 sent representatives to the newly independent Republic of Texas, where they negotiated unsuccessfully with Sam Houston et al., and the Council of 50 was scouting lands in the west in Mexican and US Oregon country.
4) Utah violence: I grew up in Provo and as a cub scout visited local pioneer museum (Veteran's Park), etc. Timpanogas were the first nations people of Utah Valley and there were was an ambush in AF canyon, and a horrible battle at Fort Utah (replica forth there now, Geneva Road just north of Center Street) where the warrior's were decaptitated and their heads put on stakes. The Chief's wife flung herself from a cliff in Rock Canyon, which became Squaw Peak. Some Indians were made slaves (research what BY said about slavery).
Research the ambush at Bear Creek in Logan. Research the Mountain Meadows Massacre and the Paiutes being blamed by BY. I now have a reverence for the First Nations people of where I grew up (Provo) and near where Angie grew up (Preston).
Brigham made bowie knife threats at the pulpit against ExMormons. A stake president in Manti had a YM castrated and there's a letter from BY to not speak of it anymore. Wild Bill Hicock claimed to have killed a dozen men for BY. A federal SLC judge was murdered, and a few weeks prior BY at the pulpit said somebody should do something about that man. When Pres Buchanan had Johnston's Army enter SLC in 1857 it was to replace BY as Territorial Gov. BY was surely concerned he would be charged for accessory in relation to the recent federal judge's death, or charged on bigamy (yes, federal anti-bigamy laws existed as early as the 1830s). BY was concerned by what might happen to him and the saints at the approaching army, so he ordered marshal law and had the temple foundation covered and most saints evacuated. By gave up his territorial governship in-part on the basis of guarantee of pardon for him and church leaders to not be charged with any crimes (bigamy, death of the federal judge, etc.).
It was during this perfectly awful 1857 time that the Fancher wagon party from NW AR entered the valley, and just six months before that (Feb, '57) Parley Pratt was murdered in the same area by an estranged husband of a married woman whom Parley married (bigamy). There were rumors that among the Fancher party were Carthage Greys and MO Wildcats, and the very pistol that killed Joseph (as if any of that would be justification for killing 120 men, women and children on their trek father down into Southern Utah in an ambush and subsequent false treaty/white flag).
Utah was entered as a Slave Territory, and you can read BY's original words that "Slavery is from God." That's the thing when people blindly follow a prophet. Yes indeed, prophets can and do lead entire groups of people (a church) astray, and that's what polygamy and racism (slavery in Utah, racial prohibition from church priesthood and temples until 1978), were.
1850s Utah was not an "all is well in Zion place." it was a time of suspicion (the second awakening/refining from church officials purging naysayers), and a time of xenaphobia and the US government replacing the mixing of theocratic/autocratic BY leadership w/territorial leadership. The worst massacre of white lives, the massacres at Bear Creek, Pleasant Grove, Ft Provo, etc. The Nauvoo Legion was still active (and activated by BY when Johnston's Army was approaching).
The legacy of victim mindset, of avenging our wrongs -- is powerful energy that lived on into the 20th century by original Mormons and their kids. We see alt-right, armed groups very active in Utah, with a belief in apocalypticism and extremism. What is that source? It's not just from the 1800s history, it's from current comments (e.g. Ezra Taft Benson was a member of the famous Burch Society, he was the one who made comments like the Civil Rights Act of 1964 was the work of communists to undermine America). https://missedinsunday.com/memes/race/so-called-civil-rights/
In summary on violence in Mormon history and its legacy effects, history is written by the victors, but the memories of First Nations people, of Fancher Party, etc. is in my heart with great respect. I also mourn the loss of Mormon lives at Huan's Mill (the worst loss of life, 18 souls). There is a reason you haven't heard about this two-sided history -- if you've only been listening to the church.
When you learn the history of polygamy (fathers/brothers who would have wanted Joseph tarred and feathered or killed for messing around with their wives/daughters/sisters), of Zion's Camp, of The Danite Mormon Militia and their burning of neighboring county seat and property and displacement of ExMos, of the Danite Malitia's attack on the Missouri State Malitia at Crooked Creek, and of Sydney's Salt Sermon (he first threatened Missourians with "extermination"); when you hear of Joseph going to Liberty jail on charges of treason, of Joseph going to jail in Carthage on charges of destruction of a press and treason (setting up a theocratic kingdom --that was the charge that had no bail); and when you see the minutes of Joseph's Council of 50 and setting himself up as King of the Earth for a theocratic Kingdom of God; and when you see the Mormons having a MO ("Danite") malitia, then the largest army (Nauvoo Legion) outside of the US Army; and when you see thugs like Porter Rockwell celebrated (he stood trial for killing Gov Boggs, and yet there's a statue of him in Lehi City Hall --- When you see all of this -- you see a two-sided story in violence and legacy-present.
Mormons now celebrate the Nauvoo Legion a type of self-defense and strength, and they celebrate murderous characters like Porter Rockwell. The feelings of one-sided victim'ness are a dangerous thing to teach, as are the narratives that "We're the one true church, Satan's hand was set against us to stir the hearts of evil men." History. Isn't. That Way. There are always two-sides, and the truth is somewhere usually in-between the versions.
It's incredibly liberating to learn the truth of history, so we can really see the truth and learn. I now see compassionately for the women victims of polygamy (whereas I used to defend the men). I now see compassionately for the First Nations victims of white, European expansion (vs believing Mormons had some of the best Indian relations in the West). Knowledge gives us a proper view, where our hearts can then align in compassion for the victims and the two-sided nature of things (vs self-victimization and self-justification). The LDS church needs to acknowledge its history and stop preaching one-sided victim'ness.