Lead: One hundred and fifty years ago the Republic was facing its greatest crisis. This continuing series examines the American Civil War. It is "A House Divided."

Intro.: A Moment in Time with Dan Roberts.

Content: After nearly half a year of Confederate victories, the spring of 1862 saw a significant shift in the opposite direction. This strategic transformation of the war inserted Union forces into the heart of the South, took back Western and Middle Tennessee, Louisiana and two state capitals, and laid the groundwork for the career of the most effective Union military leader of the war.