When James Buchanan gave his inaugural address on March 4, 1857, he was remarkably optimistic that the United States’ debate over slavery was about to end. Knowing that the Supreme Court would soon rule against Dred Scott—a man who’d escaped enslavement in the south only to be recaptured in the north—he believed this ruling would settle the debate over slavery, and urged white Americans to stop arguing about it.

“Most happy will it be for the country when the public mind shall be diverted from this question to others of more pressing and practical importance,” he stated in his address.

Yet for many people—most of all those who were enslaved—abolishing slavery was the most pressing issue, and of great practical importance. Buchanan’s attempts to appease white Americans by at times professing to take no side on slavery, and at others explicitly siding with slaveholders, inflamed divisions within the country and his own party in the lead-up to the Civil War. For this, historians consistently rank him as one of the worst U.S. presidents.

Buchanan was a Democrat from Pennsylvania whose critics referred to him as “doughface”—meaning he was a northerner with southern sympathies.

“He had very deep and intimate personal relationships with southerners,” says Thomas J. Balcerski, a history professor at Eastern Connecticut State University and author of Bosom Friends: The Intimate World of James Buchanan and William Rufus King. “Those very relationships can be said to have shaped his views during the presidency.”

In addition to being sympathetic to southern slaveholders, Buchanan wasn’t very in tune with popular opinion in the north. This may explain why he was so sure the Dred Scott v. Sandford ruling, which denied citizenship to Black people and allowed southern states to enforce slavery in free states, would end white Americans’ debate about slavery, says Michael J. Birkner, a history professor at Gettysburg College and coeditor of James Buchanan and the Coming of the Civil War.

While it was true that many white northerners weren’t concerned about slavery or the rights of Black people, they were, he says, “increasingly hostile to southern assertions of its rights at the expense of northern rights”—which was how many northerners viewed the Dred Scott decision.

Just as Buchanan failed to understand that the debate over slavery would continue after Dred Scott, he also failed to anticipate how the expansion of slavery into western territories remained a divisive issue and one that would define his presidency.

As the United States violently displaced Native Americans in western territories, white Americans moved to those territories hoping for work. Many were concerned that if slavery became legal in those territories, there would be fewer paying jobs available to white men.

The debate over slavery’s expansion was especially fierce in the territory of Kansas, where there were two competing governments.: One in Topeka wanted Kansas to be admitted to the Union as a free state (while also preventing free Black people from living there), while one in Lecompton wanted Kansas to be admitted as a slave state.

The debates between these two sides erupted in violence during a period known as Bleeding Kansas. In an attempt to resolve the crisis, Buchanan sent the Lecompton Constitution to Congress for approval, even though it represented the will of a minority of Americans in Kansas compared to the competing Topeka Constitution.

“Buchanan pushed for Kansas’s statehood as a slave state, thinking that if Kansas becomes a state, then the problem goes away,” says John W. Quist, a history professor at Shippensburg University and coeditor with Birkner of James Buchanan and the Coming of the Civil War.

Yet siding with the pro-slavery government didn’t solve the crisis. In fact, it angered northern Democrats like Stephen A. Douglas, who objected to the Lecompton Constitution because it didn’t represent the majority of the Americans in Kansas.

The debate over Kansas split the Democratic party, leading the two wings to run separate candidates for president against Republican Abraham Lincoln in the 1860 election. Kansas remained a territory until 1861, when it entered the Union as a free state during the Civil War.

The first southern secessions occurred during the “lame duck” period of Buchanan’s presidency, in the months between Abraham Lincoln’s victory in the November 1860 election and Lincoln’s inauguration in March 1861. The first to secede was South Carolina in December 1860. By February, six more states had seceded, and many of Buchanan’s southern cabinet members had resigned.

Buchanan didn’t think the seceding states had the right to leave the Union, but he also didn’t want to use military force to make them stay. As a result, Buchanan’s critics accused him of doing nothing to stop the secession crisis.

Although the Civil War was a conflict that had been building over decades—and resulted in the necessary abolition of slavery—many historians agree that Buchanan was the wrong person to be running the country in the years preceding it.

As Birkner simply puts it: “He is not the right man at the right time to be president of the United States.”