"It's not that we overlooked it," Burns said. "Our emphasis in 'The Civil War' was someplace else."
He pointed to the First Battle of Bull Run, which was treated in the 1990 documentary series as the point when both sides realized it would be a much different war than they expected and "began to gear up for a much larger campaign."
But in "Death and the Civil War," it "really had to do with the complete lack of preparation that either side had for death tolls and casualties on this scale," Burns said. "It's as if no one was in charge. It's as if no one had any idea that war was going to be fought on this scale with casualties of this tremendous number."
If the same percentage of Americans died today as did during the Civil War, the death toll would be more than 7 million. And in the 1860s, there was no system for identifying and burying the dead. No system to notify next of kin. No way to return bodies to their families. The Union Army didn't even have an ambulance corps until 1864, three years after the war began.
"That, to put it mildly, was completely new to me." Burns said. "I was sort of shocked that hiding in plain sight was this ghastly new reality [that] was cast over the entire body politic of the American people. And it changed people inside and out, North and South, black and white, in the government, in the way we bury people down to this day."
Faust, who is featured prominently in the documentary, writes and talks about how the Civil War changed 19th-century America's view of "the good death" one that was peaceful and planned for and the reality that accompanied the war.
"The book also deals with questions of meaning and religion and transformation in psychology and belief," said Faust, president of Harvard University. "And I think this film captures that part of it so magnificently the human suffering that extended not simply to those who died, but to the survivors who had to grapple with what that meant about how they understood religion, how they understood the nation state, and how they understood their lives."
"Death and the Civil War" deals with bigger questions, but it's also a gruesome reminder of the horrors of that war. The two-hour documentary is filled with shocking black-and-white photos of the fields after the battles.
"We were determined to show the war in its full gruesomeness as both the photographic record and the manuscript record would allow us access to it," Burns said. "Sometimes the gruesomeness was actually more available through the imagined horror of receiving a letter from [a soldier] as he lay dying on the battlefield at Antietam."
"Death and the Civil War" airs Tuesday, Sept. 18, at 7 p.m. on PBS/Channel 7. It's the day after the 150th anniversary of the Battle of Antietam, the bloodiest day in American history. Approximately 23,000 Union and Confederate troops were killed, wounded or listed as missing.