The third hour looks at the period from 1800 through the start of the Civil War, during which slavery saw an enormous expansion and entered its final decades.

The series' third hour looks at the period from 1800 through the start of the Civil War, during which slavery saw an enormous expansion and entered its final decades. As the nation expanded west, the question of slavery became the overriding political issue of the time. These years saw an increasingly militant abolitionist movement and a widening rift between the North - which had largely outlawed slavery but continued to reap the vast economic benefits of the system - and the South, now home to millions of enslaved black men, women and children. This is the period of slavery most commonly depicted in history books and captured by such dramas as the famed miniseries "Roots"; the segment recounts a number of personal plights just as moving as those Alex Haley chronicled. Exemplifying the kind of emotional trauma the slaves endured are Harriet Jacobs and Louis Hughes. Jacobs, born in North Carolina in 1813, grew up dodging a lecherous master and eventually fled his home, then spent seven years hiding out in her grandmother's dark, suffocating attic, watching her children from a tiny hole in the wall. Hughes and his wife, Matilda, worked together in the McGee household in Mississippi, where their newborn twins died because their mother was granted no time to feed or care for them. Decades before these stories unfolded, leading southerners such as George Washington and Thomas Jefferson had been convinced slavery was nearing its end. But the Louisiana Purchase and the Mexican War brought vast new territories into the United States, and the battle between those for and against slavery intensified. By 1860, every attempt at striking an agreement - the Missouri Compromise, the Compromise of 1850, a draconian federal fugitive slave law - had failed, splitting the Union.