Discuss the emergence of the abolitionist movement in the US in the decades leading up the Civil War. Who were the leading figures in this movement?

Many historians (myself included) stake the critical
beginning of the modern abolition movement as 1831, with the beginning of the
abolitionist newspaper The Liberator, published by William Lloyd
Garrison in Boston.  From that point, we start to see more vocal opposition to slavery,
and we see the beginning of church involvement in the years that followed with Reverend
Elijah Lovejoy and Henry Ward Beecher.

I tend to believe
that the rapid increase in the slave population during this time made the institution
impossible for the abolitionists to compromise with, or the population at large to
completely ignore. Frederick Douglass shattered myths of racial inferiority with his own
brilliant writing and speaking tours.  John Brown, the fiery radical, waged a seven year
campaign on his own to liberate slaves, one at a time if
necessary.

You also have to credit Harriet Beecher Stowe,
who published Uncle Tom's Cabin in the early 1850s, with convincing
many people of the evils of slavery, and increasing the size and energy of the
movement.