The South loses one of its boldest and most colorful generals on May 10, 1863, when 39-year-old Thomas J. “Stonewall” Jackson dies of pneumonia a week after his own troops accidentally fired on him during the Battle of Chancellorsville in Virginia. In the first two years of the war, Jackson terrorized Union commanders and led his army corps on bold and daring marches. He was the perfect complement to Robert E. Lee.

A native Virginian, Jackson grew up in poverty in Clarksburg, in the mountains of what is now West Virginia. Orphaned at an early age, Jackson was raised by relatives and became a shy, lonely young man. He had only a rudimentary education but secured an appointment to the U.S. Military Academy at West Point after another young man from the same congressional district turned down his appointment. Despite poor preparation, Jackson worked hard and graduated 17th in a class of 59 cadets.

Jackson went on to serve as an artillery officer during the Mexican War (1846-48), seeing action at Vera Cruz and Chapultepec. He earned three brevets for bravery in just six months and left the service in 1850 to teach at Virginia Military Institute (VMI). He was known as a difficult and eccentric classroom instructor, prone to strange and impromptu gestures in class. He was also a devout Presbyterian who refused to even talk of secular matters on the Sabbath. In 1859, Jackson led a group of VMI cadets to serve as gallows guards for the hanging of abolitionist John Brown.

When war broke out in 1861, Jackson became a brigadier general in command of five regiments raised in Virginia’s Shenandoah Valley. At the Battle of Bull Run in July 1861, Jackson earned distinction by leading the attack that secured an advantage for the Confederates. Confederate General Barnard Bee, trying to inspire his troops, exclaimed “there stands Jackson like a stone wall,” and provided one of the most enduring monikers in history.

By 1862, Jackson was recognized as one of the most effective commanders in the Confederate army. Leading his force on one of the most brilliant campaigns in military history during the summer of 1862, Jackson marched around the Shenandoah Valley and held off three Union armies while providing relief for Confederates pinned down on the James Peninsula by George McClellan’s army. He later rejoined the Army of Northern Virginia for the Seven Days battles, and his leadership was stellar at Second Bull Run in August 1862. He soon became Lee’s most trusted corps commander.

The Battle of Chancellorsville was Lee’s and Jackson’s shining moment. Despite the fact that they faced an army twice the size of theirs, Lee daringly split his force and sent Jackson around the Union flank—a move that resulted in perhaps the Army of the Potomac’s most stunning defeat of the war. When nightfall halted the attack, Jackson rode forward to reconnoiter the territory for another assault. But as he and his aides rode back to the lines, a group of Rebels opened fire. Jackson was hit three times, and a Southern bullet shattered his left arm, which had to be amputated the next day. Soon, pneumonia set in, and Jackson began to fade. He died, as he had wished, on the Sabbath, May 10, 1863, with these last words: “Let us cross over the river and rest under the shade of the trees.”

READ MORE: Stonewall Jackson: His Life and Legacy