I have read numerous times that the Dred Scott Decision led to the Civil War in the United States, but I have been unable to find sources to support this. It seems that the Dred Scott Decision chiefly led to other contributing factors such as the split in the Democratic Party and the rise of Lincoln.
I was wondering how, therefore, the decision actually acted as a catalyst to the Civil War, and if there were any books or reputable sources that provide a clear story.
Whole books have been written on this, and I find Frehling's two volume "Road to Disunion" books to be some of the best and most accessible evaluations of the American political landscape (as it evolved into secession) from 1776 to 1861. From the founding documents to secession, he covers a lot of ground to include the Dred Scott decision's ripple effect.
A shorter answer is as follows:
With this Supreme Court decision, abolitionists were provided grist for their public campaign against slavery because the institution of slavery, which some people in non-slave states put up with (so long as it was not legal in their state), was now viewed as being importable beyond its boundaries in the slave states. That meant that the Missouri Compromise might not stand up under the pressures from the Slave States.
That fear of the next Dred Scott decision shocked many in the North who had been content to accept slavery as long as it was confined within its then present borders. It also put the Northern Democrats, such as Stephen A. Douglas, in a difficult position. The Northern wing of the Democratic Party had supported the Kansas–Nebraska Act of 1854 under the banner of popular sovereignty. They argued that even if Congress did not bar the expansion of slavery into those territories, the residents of those territories could prohibit it by territorial legislation. The Dred Scott decision squarely stated that they could not exercise such prohibition, even though, strictly speaking, that issue was not before the Court.
While some supporters of slavery treated the decision as a vindication of their rights within the union, others treated it as merely a step to spreading slavery throughout the nation, as the Republicans claimed. Convinced that any restrictions on their right to own slaves and to take them anywhere they chose were unlawful, they boasted that the coming decade would see slave auctions on Boston Common. These Southern radicals were ready to split the Democratic Party and — as events showed — the nation on that principle.
Frehling's second volume does a fine job of addressing how the Secessionists in the South pursued their eventual ends, but that summary is sufficient for a short answer.
The two influences on politics of ideas and their presentation in the press are often significant. When someone gets an idea and beats it to death in the media, they can whip up considerable popular and political support for their position.
Another classic is the yellow journalism that got us "Remember the Maine!" and helped grow support for the Spanish American War of 1898.
The political mileage that the abolitionists got out of this court decision was of value because they took advantage of it through the press and through public rhetoric. The ripple effect of the Supreme Court decision had a contribution (probably unintentional, from the PoV of the seven justices who supported it) to both the pro slavery/secession agenda, and to the abolitionist agenda.
There were a series of compromises1 2 3 during the early 1800's designed to keep a balance between slave and free states. These generally involved Congress drawing a line on a territorial map, and decreeing that slavery would be prohibited above that line. These compromises were viewed by many as necessary to hold the country together.
Dred Scott at a stroke destroyed all those compromises, by ruling that Congress had no authority to outlaw slavery in any US territory. Southerners of course rejoiced at this. However angry northerners flocked to the new Republican Party over the next 4 years (the decision came just after the election of 1856) which had as its main platform the prevention of slavery's expansion into the territories.
