Jackson, born in what is today West Virginia in 1824 became an orphan as a boy and was raised by his uncle. Although his education was scanty, he obtained an appointment to West Point, but because of his rudimentary education, found that he had to apply himself mightily to pass his courses. Here he gained a reputation as a quiet, almost withdrawn, young man who had within him a deep resolve to make something of himself.

Jackson was commissioned as an office in the artillery and soon found himself in a war. The United States was involved in a war with Mexico, where many prominent Civil War officers learned about fighting firsthand. Jackson certainly did. In several important engagements in and around Mexico City, the young officer distinguished himself while expertly and courageously employing his cannon against the enemy. General Winfield Scott, the commanding general himself, made note of Jackson's accomplishments.

Jackson stayed in Mexico for a while and served in various Army posts, including Florida, where his exacting sense of duty and strict adherence to regulations and orders brought down the wrath of his lackadaisical post commander. This experience soured Jackson on the peacetime army and he accepted an appointment as a college professor of natural philosophy (physics) and artillery tactics at the Virginia Military Institute in Lexington. Lexington was a small, tidy town at the end of the Shenandoah Valley.

As an instructor, Jackson earned the cadets' respect over time, but his methods and personality were hard to get used to. Each night after supper, Jackson would laboriously memorize his lesson for the next day. In class, he would repeat the lesson verbatim. If interrupted by a cadet's question, he would simply repeat word for word the last section he had just spoken. Needless to say, he became a legend. Cadets called him "Tom Fool" Jackson.

He was also a hypochondriac, always imagining some imbalance in his body. As a result, he ate only milk and corn or whole wheat bread to assist his digestion and sat bolt upright in his chair, like a sculpture of an Egyptian pharaoh, to ensure his internal organs were properly aligned. He was also deeply religious, following the rules of the Bible as if they were a set of military regulations. He established a Sunday school for slave children in town.

He married twice, his first wife dying in childbirth - not an uncommon occurrence in nineteenth century America. He remarried and bought a house in Lexington and was very happy with his situation. Jackson and the VMI corps provided a military presence for the execution of John Brown. John Brown was not the end, but only the beginning of sectional strife that would lead to war. When the war came, Jackson, like so many others living quiet, contented lives, joined the colors when his home was threatened. Taking a detachment of cadets to Richmond to assist with drilling new recruits, Jackson was dispatched to Harper's Ferry to train new soldiers there.

Jackson had no time for the relaxed atmosphere of sunshine soldiers. He drilled the men hard and established firm discipline. Jackson had a full beard and piercing blue eyes. He was awkward in his manner, careless in his dress, wearing the military coat he wore in Mexico and he wore a battered cap pulled low over his eyes. He had no interest in the pomp and circumstance of the parade ground or the privileges of rank that some officers sought. Quiet, serious, seemingly preoccupied, Jackson always put his duty as a soldier first above everything else and was uncomprehending when others did not do the same.

Although thoroughly disliked by his new trainees, Jackson cared not a whit. War was serious business and called for stern measures. He would follow his orders and do his duty. Jackson did his job well. The same unit he trained at Harpers Ferry he led on the Manassas battlefield in the first major action of the war. The brigade stood out as calm and ordered amid the confusion and terror of battle - a direct result of Jackson's stern and demanding discipline. As a reward for his exceptional performance at the Battle of Manassas, Jackson was given command of a small army of 4,200 men with the mission of defending the Shenandoah Valley.