Jackson acquired his nickname, July 21, 1861 on Henry Hill outside Manassas, in the Battle of First Bull Run (First Battle of Manassas). Infantry under South Carolinian brigadier general Bernard Bee had been engaged for some time and were falling back; Jackson's brigade was in reserve. Bee told his men: "There stands Jackson like a stone wall". When Jackson threw his troops into the battle, they captured Union artillery atop the hill and fought the Federals until Confederate reinforcements caused a Union rout.

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