Pierce settled in New Hampshire after his presidency. When the Civil War erupted, Pierce voiced support for the Northern cause, as did many doughfaces—that is, Northern men with Southern principles. A loyal Democrat, Pierce did not support the new President, Abraham Lincoln. In fact, Pierce publicly blamed Lincoln for the war. This outspoken criticism cost the former President a number of longtime friendships.

By the end of the war, Franklin Pierce was all but forgotten, as reclusive as his wife had been in the White House. Always fond of liquor, he had returned to it. When Lincoln was assassinated in April 1865, an angry mob surrounded Pierce's home. Only a final display of the old lawyer's once-famed oratorical skills kept his house in one piece: he gave a speech urging the crowd to disperse peacefully, and they did. When Franklin Pierce died in the fall of 1869, little was written about him.