Complex sentence: Stonewall Jackson was shot and mortally wounded in Spotsylvania County during the Battle of Chancellorsville, when a group of Confederate soldiers from North Carolina who were in the woods heard General Jackson's party returning from a reconnaissance of Union lines.
Split into simpler sentences: Stonewall Jackson was shot and mortally wounded in Spotsylvania County during the Battle of Chancellorsville. A group of Confederate soldiers from North Carolina were in the woods when they heard the footsteps of General Jackson's party returning from a reconnaissance of Union lines.