There were a number of crises in the 1850s in the United States. They helped to cause the Civil War to come about.
One of these crises was the one caused by the Dred Scott decision. This decision made it impossible for the Congress to make any laws about slavery in the territories. This made compromises like the Missouri Compromise or the Compromise of 1850 impossible.
Another crises arose out of the Compromise of 1850. This came about in reaction to the Fugitive Slave Law. Many Northerners opposed and hated this law. Their resistance to the law angered Southerners.
The greatest crisis, however, was the one that followed the Kansas-Nebraska Act. This led to the actual fighting in "Bleeding Kansas." All of these crises helped to bring on the Civil War.