By Samuel Wheeler, Ph.D., Illinois Supreme Court Historic Preservation Commission
From its earliest days as a frontier territory, Illinois did not treat divorce as a private matter but as a public concern shaped by moral and social anxieties. Many early divorces were accomplished with legislative acts, not in a courtroom. As Illinois grew from an agrarian frontier to a large industrial state, lawmakers repeatedly revised the divorce code to address new social realities. By 1900, rising divorce rates sparked fears that traditional family structures were eroding. Moral reformers encouraged the Illinois General Assembly to intervene. Lawmakers responded by enacting a controversial, though largely forgotten, law that required divorced residents to wait at least one year before marrying again.
After statehood, the first Illinois General Assembly codified divorce law. “An Act concerning Divorces” laid out the grounds for divorce and required the party seeking dissolution to prove the charges in open court. Illinois amended its divorce statutes several times, culminating in an 1874 code that consolidated prior laws and listed specific grounds for divorce, such as adultery, desertion, extreme cruelty, habitual drunkenness, and abandonment. Cases were heard in chancery court and required corroborating testimony, making the proceedings public and sometimes painful.
By 1900 industrialization, urban migration, and new gender expectations contributed to a sharp rise in divorce rates. Moral reformers warned that marriage was becoming too easy to exit and urged lawmakers to slow the trend. In 1905 the General Assembly responded by adding Section 1a to the existing Divorce Act, requiring divorced individuals to wait one year before remarrying and two years if adultery were the proven divorce grounds. Violations could bring jail time. Lawmakers argued this “cooling-off period” would prevent rash remarriages and protect public morals.
Many Illinoisans simply left the state to remarry. One example was Robert Cook, who had been granted a divorce in November 1906 in St. Clair County. Three months later, he married a widow named Mary Alice Moore in St. Louis. The couple lived together on her 40-acre farm in Madison County.
When Mary died in 1912, her brother, Robert J. Wilson, administered her estate and sought to sell the farm to pay her debts. Cook objected, claiming marital rights to the property. Wilson argued that Cook was never legally married to his sister because the wedding took place in violation of the required one-year waiting period. The Madison County Probate Court sided with Wilson and declared the marriage invalid. Cook appealed to the Illinois Supreme Court.
In Wilson v. Cook, 256 Ill. 460 (1912), the Illinois Supreme Court affirmed the ruling, holding that Illinois residents could not evade the law by simply marrying in another state. Allowing such conduct, the court wrote, would make the law “useless and impotent.”
The decision threw many families into uncertainty. Critics argued the law punished good-faith spouses and, most troubling, cast doubt on the legitimacy of children born to such unions. By 1923 legislators acknowledged the law’s unintended consequences and repealed Section 1a. Afterward, Illinoisans could remarry as soon as their divorce was finalized.
Over the next half-century, Illinois continued to liberalize its divorce laws, culminating in “The Illinois Marriage and Dissolution of Marriage Act of 1977,” which established the state’s modern framework for divorce. In 1984, the Act was amended to add “irreconcilable differences” as a no-fault ground, while preserving the traditional fault-based system. In 2016, Illinois abolished all fault-based grounds entirely, making “irreconcilable differences” the only basis for divorce in the state.