We had memoires and diaries from a good number of ancestors that dated back several centuries including a family lineage that had a passed down history that dated back to the 1000's.
All of that as well as more modern family military records were in the care of my Aunt, who developed dimensia and allowed all the stored records to become ruined by water damage. All of it, including tins full of photographs were lost.
It was hard to accept all that history being lost, doubly so with my Aunt, who succumbed to Alzheimer's and passed away.
In regards to the Civil War, we had a number of relatives on both sides, like Ascil Wood, a Union private who was killed at Shiloh and Gen. Robert Lilley of the Confederate States Army.