Why was chickamauga important to the north and the south?

Chickamauga was the largest Confederate victory in the Western theater. With 16,170 Union and 18,454 Confederate casualties, the Battle of Chickamauga was the second costliest battle of the Civil War, ranking only just behind Gettysburg, and was by far pretty much the deadliest battle fought in the West.

it is a better alternative

you answered your own : -/