Why was Joseph Smith killed?

The sources identify several contributing causes rather than a single motive. The volume introductions connect criticism and threats against Smith to controversial teachings, plural marriage, his growing political power, and other factors. They identify opponents both among disaffected church members and in surrounding communities.[1][5]

The Nauvoo Temple podcast transcript explains that some Illinois residents feared the concentration of religious, civic, political, and economic power in Nauvoo. The Saints’ bloc voting heightened these concerns because it could determine closely contested elections. Critics also believed Nauvoo’s charter placed Smith above the law, whereas Smith and others regarded its powers as necessary protections for their rights.[7]

Threats against Smith’s life preceded his final imprisonment. His journal entry for 27 May 1844 reports that Charles A. Foster warned him of a conspiracy and that Robert D. Foster said some people were determined he should not leave Carthage alive. The entry also reports that Joseph H. Jackson was seen loading his pistol and threatening Smith and Hyrum.[2]

The immediate sequence leading to the killings involved the Nauvoo Expositor. After Nauvoo civic leaders declared the newspaper a public nuisance and destroyed its press, Smith and several associates were arrested.[1] At Carthage, Joseph and Hyrum were arrested again on treason charges and jailed on the evening of 25 June. A mob killed them there on 27 June.[3][5]

These excerpts therefore explain the killing through a combination of broader hostility and an immediate crisis over the newspaper’s destruction and Smith’s imprisonment; they do not establish a single motive shared by every member of the mob.[1][3][7]