What role did stonewall Jackson at the second battle of bull run?

Answer 1

No, Jackson was a one star brigadier general at that point, during the First Battle of Bull Run. The Rebels had about fifteen brigades or so, each with its own commander. Jackson had probably 2-3,000 troops under his direct command. The highest ranking Confederate present was General Joseph E. Johnston, but he had just arrived and was unfamiliar with the ground and the positions of the Confederate troops, so he allowed General Pierre G. T. Beauregard to continue to direct the battle.

The next year, at the Second Battle of Bull Run, Jackson was a three star general commanding a corps. Jackson's corps was alone on the first day of the battle, opposing the entire weight of the Yankees. Late on that day the other corps of Lee's army arrived on the battlefield, along with Lee himself, and the next day the Union army was again defeated on the field at Bull Run.

Answer 2

That is a rather lengthy and involved answer. This contains a good summary of the battle: https://en.wikipedia.org/wiki/Second_Battle_of_Bull_Run