Documentary Review: American Experience: Death and the Civil War (2012)

After the initial fuss was over, the North and the South settled into real war, and the casualty figures were such that neither side was prepared to death with the slaughter, with the dead.  There was no way in tact for getting bodies home, nor was there proper burial details to inter the bodies where they were.  Bodies lying battlefield, and subsequent photographic essays of these bodies brought the carnage home to the citizenry. 
Even though the paper would publish military records of the deceased, often these were incomplete, or mistakes were made.  If it listed someone as wounded, they often later died.  There were demands for change.  This started with volunteer societies, including Clara Barton's, which brought some relief.  Still many bodies were interred in mass graves, and many were left unburied.  There were some improvements, and a Union organization helped with some reclamation of bodies, but even at the end of the war there was much to do.  On the Union side, Clara Barton published stories in papers.  Sometimes this lead to closure.  Money was expended for the recovery of bodies and a commission set up, after convincing the government that they were responsible to see the bodies were returned home.  These efforts lead to the ability to locate many bodies, and the establishment of National Cemeteries on battlefields throughout the country.  Those of Southern extraction, noted that Confederate troops were left out, and eventually provision was made for the search of these bodies as well.  on the Union side 55 percent of the deceased were identified.  The statistics were worse for the Southern soldiers.  Many were left in unmarked graves.
You may also want to review this essay by Walt Whitman
http://bwardlehistory.blogspot.com/2014/02/walt-whitman-prose-of-dead-of-civil-war.html
or this previous post on death and the Civil War.
http://bwardlehistory.blogspot.com/2013/11/us-civil-war-people-became-acquainted.html
The American attitude toward death, and military death in particular changed as a result of the war.  Since there has been greater effort to get the remains home.  Also Memorial Day was established as a time to remember our fallen soldiers. 
This movie can be graphic, but it does make you stop and think.