Definition:
The Crittenden Compromise was a series of proposed Constitutional amendments introduced in the United States Senate in December 1860 by Senator John Crittenden of Kentucky. The proposals were a final attempt to avert the Civil War by arriving at an accommodation between the slave states of the South and the free states of the North.
Crittenden had been a longtime follower of his fellow Kentuckian Henry Clay, who had been involved in the Missouri Compromise of 1820 and the Compromise of 1850.
Apparently inspired by the work of Clay, Crittenden's suggestions to change the U.S. Constitution were extremely ambitious.
Had Crittenden's proposals been enacted, it is possible that the Civil War may not have started. But given the broad scope of his proposals, not to mention the intense crisis which was already unfolding following the election of 1860, the chance of success was never great.
Despite some public expressions of support for Crittenden's proposals in both the North and South, when they were brought up for a vote in the U.S. Senate they failed to pass.