United States History On This Date: May 18th

1652 — Rhode Island Bans Slavery

The colony of Rhode Island enacted the first law in North America prohibiting lifelong slavery, declaring that no person could be held in bondage for more than ten years. Though the statute was poorly enforced and often ignored, it marked an early legislative challenge to the institution of slavery. The measure foreshadowed the region’s later leadership in abolitionist activism and moral reform.

1860 — Republican Convention Nominates Abraham Lincoln

Delegates meeting in Chicago selected Abraham Lincoln as the Republican nominee for president, surprising many who expected William Seward to prevail. Lincoln’s moderate tone on slavery and his reputation for integrity helped unify the party’s diverse factions. His nomination set the stage for the most consequential election in American history, one that would unfold against the rising storm of sectional crisis.

1896 — Plessy v. Ferguson Upholds Segregation

The U.S. Supreme Court ruled 7–1 that racial segregation laws were constitutional under the doctrine of “separate but equal.” The decision legitimized Jim Crow statutes across the South and entrenched racial discrimination for decades. Justice John Marshall Harlan’s lone dissent warned that the ruling would prove disastrous for American liberty—an assessment history would later confirm.

1980 — Mount St. Helens Erupts

A massive volcanic eruption in Washington State sent ash thousands of feet into the air, flattened forests, and triggered deadly mudflows. The blast killed 57 people and reshaped the mountain’s profile, creating one of the most dramatic geological events in modern U.S. history. The eruption prompted major advances in volcanic monitoring and emergency preparedness nationwide.

Mount St. Helens eruption kills 57 people