The Causes of the Civil War

Iowa became a state in 1846. The United States at that time was divided into two very different sections. In the northern states most Americans were white. They owned small farms, worked in factories or ran small shops. In southern states white and black Americans lived together and farming was the major industry. Most African-Americans in the South were slaves. They had no voice in making the laws that kept them in slavery. The law said they were the property of their white owners. 

The Missouri Compromise

Settlers from both North and South were moving west. The nation had to decide whether new states would allow slavery or not. In 1820 Congress passed a law they hoped would solve the problem. The Missouri Compromise drew a line from the Mississippi River to the Pacific Ocean. Slavery would be allowed south of that line but not north of it. Because Iowa fell far north of the line, Iowa came into the Union as a “free” state without slavery.

Iowans were divided about the slavery issue. Like most white Americans of their time, most white Iowans believed they were smarter and more civilized than African-Americans. They believed that the United States should be a country for white people only. They did not object strongly to slavery where it existed in the South, but they did not want to live next to slaves or compete with slave labor. Some joined a new political party, the Republican Party, that opposed the spread of slavery. A few Iowans were “abolitionists” because they wanted to “abolish” slavery wherever it existed.

The Kansas-Nebraska Act

In 1854 Congress passed a new law, the Kansas-Nebraska Act. The law allowed the white settlers in each new state to decide whether they wanted slavery or not. Most Iowans opposed the new law. They already had a slave state, Missouri, on the southern border. Now there was a possibility of slavery in the territories to the west, in Kansas and Nebraska.

Kansas became a battleground. Settlers from both northern and southern states began moving there, and fighting broke out. Because Iowa was the closest northern state, the little town of Tabor in the southwest corner of Iowa became a gathering place for groups of northern settlers moving to Kansas. Tensions mounted even more when a fiery abolitionists named John Brown led a raid in Virginia. He hoped to lead a slave revolt to end slavery forever. He had recruited six Iowans and trained in the little Quaker community of Springdale. His effort failed. He was quickly captured and hanged for treason. Some of his men escaped.

The tension increased in both the North and South. In 1857 the United States Supreme Court ruled that slaves were property and had no rights. They could be taken anywhere in the United States, just like cattle or furniture. Many people in the North were outraged. Did this mean that slavery could exist everywhere, Iowa included?

Presidential Election

The slavery question was the most important issue in the election of 1860. The new Republican Party nominated Abraham Lincoln who was opposed to the spread of slavery into any new territories where it did not already exist. Because the Democrats could not agree, they split. Northern and southern Democrats each nominated a candidate. States on the border between North and South also supported a candidate pledged to finding a compromise.

Abraham Lincoln won the election but with only about 40 percent of the vote. His support was entirely from the North. His name was not even on the ballot in many southern states. The southern states feared that the election of Lincoln meant the national government would now work against them.

Iowa voted for Lincoln, and the Republican Party won most of the state contests. However, even before Lincoln was sworn in as president, several southern states decided to “secede,” to withdraw and form their own nation.

In 1861 the United States was falling apart.


When discussing the causes of the Civil War, the raid at Harpers Ferry has sometimes been referred to as "the spark that ignited the powder keg." What do you think is meant by this reference?

Media Artifacts

Reading Tip: Reading for Meaning
Can you list all of the cases of the Civil War that were listed in this article? If not, reread the article and make a list of the causes.