This is the story about an old Civil War veteran who lives with his son and grand-daughter. The old man's son remarries and his new wife is a bit of a stick-in-the-mud and is greatly put off by grandpa's drinking. So, not wanting to be in the way or a bad influence on his grand-daughter, the old man leaves. He writes to tell them things are fine but he's really living at the poor house! Later, the crusading daughter-in-law visits this same poor house with her crusading friends--only to see the man in his pitiful state. This is where the film goes overboard on the melodrama--but not so much that it ruins the film.
The final section of the film is the most important. It shows actual memorial services and Civil War veterans at these ceremonies. As such, it is a super-important historical record that should not be forgotten or lost. To me, an American History teacher, this is where the film makes its biggest impact.