The Legal and Social Challenges of Plural Marriage in the 19th Century

Why polygamy created legal chaos, social outrage, and a clash between religious freedom and government power in 1800s America.

By Garret Merkley · Explainer · Jun 16, 2026

Branched from Daily Life and Household Dynamics in 19th-Century Plural Families

Quick take

Plural marriage was illegal in most U.S. states but practiced openly by Mormons, creating a direct conflict with federal law.
Courts stripped polygamists of property rights, citizenship, and child custody—using the law as a weapon to suppress the practice.
Social opposition came from mainstream Americans who saw plural marriage as immoral, while some women's rights advocates weaponized anti-polygamy sentiment for their own causes.
The conflict lasted decades and only resolved when the LDS Church officially abandoned polygamy in 1890, showing how legal pressure can override religious doctrine.

Plural marriage—one man with multiple wives—was practiced openly by members of the Church of Jesus Christ of Latter-day Saints (LDS or Mormon church) beginning in the 1830s, but it collided head-on with American law, which treated it as bigamy and a criminal offense. This wasn't a quiet religious practice tucked away; it was visible, defended by church leaders as divinely ordained, and directly challenged the legal and moral foundations that mainstream American society believed it stood on. The result was a decades-long legal and cultural war that pitted religious freedom against state power, exposed deep anxieties about women's rights and family structure, and ultimately forced the LDS Church to choose between its core doctrine and political survival.

How the Law Treated Plural Marriage

Bigamy—marriage to more than one person—was a crime in every U.S. state by the 1800s. When the LDS Church began practicing polygamy openly in Utah Territory in the 1850s, federal authorities had a legal framework ready to prosecute it. The problem was enforcement: Utah was a remote territory with a Mormon majority, and local juries were often sympathetic to defendants. So Congress escalated. The Morrill Anti-Bigamy Act of 1862 made polygamy a federal crime and allowed prosecution in federal courts, where judges were appointed by Washington rather than elected locally. This was a direct assertion of federal power over a religious practice in a territory.

The courts went further than just criminalizing the act. They used property law and family law as levers. Polygamists could be stripped of real estate, denied business licenses, and excluded from voting. Children born in plural marriages faced legal uncertainty about inheritance and legitimacy. Women in plural marriages had no legal standing to claim a husband's estate—courts treated them as concubines rather than spouses. These weren't accidental side effects; they were deliberate legal penalties designed to make polygamy economically and socially untenable. By the 1880s, federal marshals were aggressively prosecuting LDS men, and the church faced the prospect of losing control of its own institutions in Utah.

Why Mainstream America Was Outraged

Opposition to plural marriage wasn't purely legal—it was visceral and moral. Mainstream American Protestants, Catholics, and secular reformers saw polygamy as un-Christian, uncivilized, and a threat to the nuclear family structure they believed was the foundation of a stable society. Newspaper editorials routinely denounced it as Oriental despotism transplanted to American soil. But the opposition also had a gendered edge: many critics genuinely believed that plural marriage exploited women, turning them into property and denying them the legal protections of monogamous marriage. This created a strange alliance: some early women's rights advocates supported anti-polygamy laws, even though those same laws limited women's legal autonomy in other ways. They saw suppressing polygamy as a way to protect women from what they viewed as degradation.

There was also a nativist and anti-Mormon dimension. Non-Mormon settlers in Utah resented LDS political and economic dominance. Federal officials saw the church as a rival power structure that refused to submit to American law. Polygamy became a symbol of the LDS Church's defiance and its separateness from mainstream American culture. Eliminating it wasn't just about morality—it was about asserting federal authority and forcing Utah (and the LDS Church) to conform to American norms as a condition of statehood.

The Clash Between Religious Freedom and State Power

The LDS Church argued that plural marriage was a religious practice protected by the First Amendment's guarantee of religious freedom. Church leaders like Brigham Young insisted that the government had no right to criminalize a practice that was central to their faith. The Supreme Court disagreed. In Reynolds v. United States (1879), the Court ruled that religious belief does not exempt someone from obeying criminal laws of general applicability. In other words: you cannot break a law just because your religion tells you to. This principle became foundational to American religious liberty law, but it also meant that the government could enforce a uniform moral and legal code even against sincere religious practice. The church had lost the constitutional argument.

Why This Mattered and When It Peaked

The plural marriage conflict was the defining civil rights crisis of the late 19th-century American West. It forced a reckoning with questions that still echo today: How much power should government have to regulate intimate family life? When does religious freedom end and civil law begin? Can the state use law to suppress a minority religious practice? The conflict also exposed how anti-polygamy sentiment could be weaponized—mainstream Americans used women's welfare as a justification for laws that actually constrained women's legal agency in other contexts. By the 1880s, the pressure was unbearable. Federal prosecutions intensified, the church lost property in court cases, and Utah could not achieve statehood without abandoning polygamy. In 1890, church president Wilford Woodruff issued the Manifesto, officially ending the practice. The legal battle was over, but only because the church capitulated.

Key Legal Milestones

1862: Morrill Anti-Bigamy Act makes polygamy a federal crime.
1879: Reynolds v. United States establishes that religious belief does not exempt you from criminal law.
1882: Edmunds Act increases penalties and allows prosecution of 'unlawful cohabitation' (living with more than one spouse), not just formal marriage.
1887: Edmunds-Tucker Act dissolves the LDS Church as a corporation and seizes its property.
1890: LDS Church issues the Manifesto, officially discontinuing plural marriage.

Was plural marriage actually practiced widely, or was it a small fringe thing?

It was practiced by a significant minority within the LDS Church—estimates suggest 20–30% of LDS families included polygamy at its peak in the 1870s–80s. But it was concentrated among church leaders and wealthier members. Most LDS members were monogamous, and the practice was always controversial even within the church. The visibility and defiance of church leaders made it seem more widespread and provocative than it actually was.

Did the government's anti-polygamy laws actually work?

Yes, combined with social pressure and the church's own capitulation. Prosecutions, property seizures, and the threat of losing statehood made the practice unsustainable. After 1890, polygamy declined sharply among mainstream LDS members, though small fundamentalist groups continued practicing it illegally. The legal and economic pressure was decisive.

What happened to women in plural marriages when the practice was outlawed?

Many faced legal and economic hardship. They had no claim to their husband's estate, could not claim spousal benefits, and faced social stigma. Some were abandoned by their husbands, who married new monogamous wives to stay within the law. The church eventually provided some support, but women in plural marriages bore the cost of the legal crackdown. Ironically, the laws meant to protect women often harmed them.

Could the church have won the Reynolds v. United States case?

Very unlikely. The Supreme Court was interpreting the First Amendment in a context where there was overwhelming public opposition to polygamy and a strong consensus that the federal government had the right to regulate marriage. The principle the Court established—that neutral laws of general applicability can restrict religious practice—was legally sound and politically popular. The church's only real option was to abandon the practice.

Does this case still matter for religious freedom today?

Absolutely. Reynolds v. United States is still cited in cases involving religious exemptions from general laws. It established that sincere religious belief alone does not create an exemption from criminal law, which remains the baseline principle in American religious liberty jurisprudence, though courts now apply some additional tests to balance religious freedom against government interests.

Sources

Reynolds v. United States, 98 U.S. 145 (1879)—Supreme Court decision establishing that religious belief does not exempt from criminal law.
Morrill Anti-Bigamy Act of 1862 and subsequent Edmunds Act (1882) and Edmunds-Tucker Act (1887)—federal legislation targeting polygamy in U.S. territories.
LDS Church Manifesto of 1890—official statement discontinuing plural marriage.