Image source: Library of Congress
On my mother's side of my family I have six ancestors who fought in the Civil War. But a quick look at her family tree gives me at least eleven more soldiers - and that's before I get ambitious and look beyond uncles and first cousins. Of that whole group the man I've studied the most about is David Marlin, who died at Gettysburg. He was a 2nd Lt with the Second Mississippi Infantry, Company H. He made it through the battle in the railroad cut, gaining command of his company when his captain was injured there. That gave him the dubious honor of leading his men onto the field as part of Pickett's charge. He died the morning of July 3, 1863 and we will likely never have a grave to lay flowers on.
I've often wished I could say my ancestor died at Gettysburg, if only because it's easier than saying my great-great-grandfather's brother was in that historic battle. But David isn't technically my ancestor. An ancestor, as Merriam Webster tells us, is "one from whom a person is descended" and David isn't in my direct line. Instead he's what genealogists call an indirect or collateral relative. He's related to me by blood not marriage. But he's not someone I can describe with the word father or mother in the title - not in the straight line up my tree. So - does that matter?
In some places, yes, it matters a lot. Most of the lineage societies (organizations based on family ties) require members to be direct descendants of someone in the group they are honoring. You can't join the Mayflower Society unless you are descended in a straight line from somebody who was on that ship. Both the Daughters and Sons of the American Revolution also require you have a direct ancestor who aided in the fight for American Independence. The Sons of Union Veterans of the Civil War are the same.
When it comes to the Confederacy, though, the rules are a bit different. Both the Sons of Confederate Veterans and the United Daughters of the Confederacy accept both direct and collateral descendants of Confederate soldiers. I haven't seen any explanation as to why these organizations decided to broaden their definition of ancestor (if you know - please share!).
In the end, the words don't matter to me. David had no children so keeping his memory alive is something only his collateral descendants can do. As I keep adding to my family tree I keep adding soldiers who fought in the Civil War and I keep gathering their stories too. Ancestors or not, they matter.