Thomas Jonathan 'Stonewall' —, Confederate brigadier general associated with the First Battle of Bull Run of 1861 during the American Civil War (7)
I believe the answer is:
jackson
(Other definitions for jackson that I've seen before include "American hero" , "Mississippi capital and 7th US president" , "American painter, 1912-56" , "See 13" , "Seventh US president Andrew - actress turned politician Glenda - singers Michael and Janet etc" .)