William Henry Powell (May 10, 1825 – December 26, 1904) was an American soldier who fought for the Union in the American Civil War. He was a leader in the iron and nail business before the war, and his leadership abilities proved useful in the military. Powell began as a captain, and quickly ascended to higher roles in the cavalry, including commanding a regiment, a brigade, and then a division. Powell was awarded his country's highest award for bravery during combat, the Medal of Honor, for heroism at Sinking Creek, Virginia, when, as leader of a group of 22 men, he captured an enemy camp and took over 100 prisoners. This was accomplished without the loss of any of his men on November 26, 1862. He was honored with the award on July 22, 1890.

In July 1863, Powell was shot while leading cavalry in Wytheville, Virginia. Although surgeons on both sides of the conflict believed his wound was fatal, Powell survived—and became a prisoner of war. He was later exchanged, and returned to his command of the 2nd West Virginia Volunteer Cavalry Regiment. In 1864, Powell commanded brigades while fighting mostly in the Shenandoah Valley under the direct supervision of General William W. Averell in an army commanded by General Philip Sheridan. Eventually, Powell replaced Averell as division commander. Powell led cavalry in numerous battles, including Moorefield, Opequon, and Fisher's Hill. He resigned as a brigadier general in January 1865 to tend to family health issues. He was later brevetted to major general. Powell returned to his original profession working in the iron making industry, and was active in the Grand Army of the Republic, a fraternal organization of Union veterans of the American Civil War.

In a letter sent to headquarters in 1864, General George Crook said "Colonel Powell has served with me often since the commencement of the war. He has distinguished himself in every battle he was engaged in under me. He has been recommended by me on several occasions, for promotion. I regard him as one of the best cavalry officers I have ever seen in the service."

Early life William Henry Powell was born on May 10, 1825, in Pontypool, South Wales. At the time, the community was part of Monmouthshire, an iron-making region. Both of his parents, William and Sarah Griffith Powell, were Welsh. His father immigrated to the United States in 1827, and his mother followed in 1830 with the rest of the family. Originally, they lived in New Jersey and Pennsylvania, but they moved to Nashville, Tennessee, in 1833. Powell's father was an ironworker, and was employed by the Gennessee Iron Works. Powell began to learn his father's profession while still a boy, working in a rolling mill and nail factory in Nashville. In 1840, the Gennessee Iron Works closed because of a recession. The family moved north to Wheeling, Virginia, in 1843. Powell's father began employment at Wheeling's Rolling Mill Nail Factory.

Powell continued learning his father's profession in Wheeling. Four years after the move to Wheeling, he built the Benwood Nail Works while only 22 years old, and became its superintendent. In 1846, he was involved in an accident at the nail iron works and lost vision of his right eye. Powell married Sarah Gilchrist in 1847, and they eventually had six children. Two children died in infancy, and one died at age 20. In 1853, the family moved to Ironton, Ohio, which is located southwest of Wheeling along the Ohio River. In Ironton, Powell built the Bellfonte Nail Works. When the American Civil War began in 1861, Powell was general superintendent and financial agent of this large iron works. He left the business in August to begin service as a cavalry captain.

American Civil War: Western Virginia Between September 20, 1860, and February 1, 1861, seven southern states seceded from the United States and formed the Confederate States of America. Fighting began on April 12, 1861, when American troops were attacked at Fort Sumpter in South Carolina. This is considered the beginning of the American Civil War. Four additional states, including Virginia, seceded during the next three months. Some of the northwestern counties of Virginia disagreed with secession and they met in Wheeling to form a Restored Government of Virginia loyal to the United States.

Initially, the "War of the Rebellion" was not expected to last long. However, the war continued through the summer, and President Abraham Lincoln called for volunteers to fight against the rebels of the Confederacy. Powell resigned his civilian job on August 1, 1861, and recruited enough men to form a company of cavalry and was elected their captain. Ten companies were united to form a cavalry regiment which consisted mostly of men from the Ohio counties located close to the Ohio River. The regiment was originally intended to be the 4th Ohio Cavalry, but Ohio governor William Dennison refused to accept the unit's application because he had been instructed to accept no more new cavalry. The regiment's application was accepted by the provisional governor of the Restored Government of Virginia, Francis Harrison Pierpont, and became the 2nd Regiment of Loyal Virginia Volunteer Cavalry. Powell's company was designated Company B, and he was commissioned as its captain on August 14. The regiment's first significant action was on January 7, 1862, in Louisa, Kentucky, where it assisted a force commanded by Colonel James A. Garfield, future President of the United States. Powell led his company, reinforced with men from the regiment's Company C, in a charge that drove back a Confederate rearguard.

Kanawha Valley During 1862–1863, the 2nd Loyal Virginia Cavalry spent much of its time confronting bushwhackers—who were despised. The bushwhacker was thought of as an "unprincipled scoundrel who was too cowardly to join the army and fight as a man…", who would "sneak around like a thief in the night…." Eventually, Union forces in the mountains of what became West Virginia became very ruthless in their treatment of bushwhackers.

Powell was usually stationed near the Kanawha River Valley, in the southwestern portion of present West Virginia—which was part of Virginia at the time. Entire regiments were not needed for bushwhacker duty, so the regiment often worked in detachments of two companies. In April 1862, Powell's regiment was divided into two battalions. Powell's battalion, commanded by Colonel William M. Bolles, joined some Ohio infantry regiments to form the 3rd Brigade of General Jacob Dolson Cox's Kanawha Division. The brigade was commanded by Colonel (later Major General) George Crook, a professional soldier with fighting experience in the American West. Crook's brigade normally operated independently from the other portion of Cox's division. Its camp was located at Meadow Bluff, west of Lewisburg in Greenbrier County.

Powell's major fighting experience as part of this brigade happened on May 27, against Confederate General Henry Heth. Crook's brigade ambushed Heth's force in Lewisburg, killing or wounding over 150 enemy soldiers and capturing over 150. The cavalry pursued the fleeing rebels and stopped only when a bridge was destroyed. Shortly after this engagement, Colonel Bolles resigned and several officers of the 2nd Loyal Virginia Cavalry were promoted. On June 25, 1862, Powell was promoted to major because of his gallant conduct in Kentucky and to fill a vacancy caused by the Bolles resignation.

Kanawha Valley Campaign During August 1862, many of the Union soldiers stationed in western Virginia were sent to Washington to reinforce the Army of Virginia. This caused the two battalions from the 2nd Loyal Virginia Cavalry to be reunited, and it was stationed with two infantry regiments in Kanawha Falls, close to Gauley Bridge, in what is now south central West Virginia. The small force was commanded by Colonel Joseph Andrew Jackson Lightburn.

In September, the Confederate Army became aware of the Union Army's lack of manpower, and devised a plan of attack. The Confederates sent a large force led by General William W. Loring, incorrectly rumored to be 10,000 men, to attack Lightburn from the southeast. A cavalry brigade of about 550 men led by Colonel Albert G. Jenkins patrolled along the Ohio River with the intention of preventing a retreat by Lightburn. A large portion of the 2nd Loyal Virginia Cavalry, commanded by Colonel John C. Paxton, was sent to confront Jenkins. Powell led the advance guard, which happened to be Powell's company (CompanyB) before his promotion to major. On September 8, Powell's advance group led the attack on Jenkins' rebel camp outside of Barboursville, which is close to the Ohio River. The camp was captured, and Jenkins barely escaped. The rebel force, which was much larger than Paxton's cavalry, was driven southward up the Guyandotte River.

Thus, Powell's advance guard for Paxton enabled a safe retreat to the Ohio River for the remaining portion of Lightburn's small force. Lightburn's report said "The Second Virginia Cavalry, under Colonel Paxton, did good service in keeping Jenkins' force at bay, thereby preventing an attack in our rear. I wish, also, to state that Colonel Paxton, with 300 men, attacked Jenkins' whole force (from 1,200 to 1,500), and drove them from Barboursville, which, no doubt, kept them from an attempt to harass our retreat."

Sinking Creek raid

Confederate gains in the Kanawha Valley did not last long, and Union troops reoccupied much of the valley. In November 1862, the 2nd Loyal Virginia Cavalry camped for the winter along the Kanawha River, about upriver from Charleston. Newly promoted Brigadier General George Crook commanded Union troops in the valley, and Paxton commanded Powell's regiment, the 2nd Loyal Virginia Cavalry. Crook was an experienced Indian fighter, and believed that adverse weather was an advantage in the hit-and-run fighting style of raids. On November 23, he ordered Paxton to rendezvous with an infantry regiment on Cold Knob Mountain, and then lead an attack on two rebel camps in Sinking Creek Valley. Before the cavalry regiment departed, Crook confidentially told Powell to not return without good results.

The cavalry reached their meeting place near the top of Cold Knob Mountain on November 26. The 11th Ohio Infantry had arrived a few hours earlier. The men from the infantry had marched through rain, and were caught (as was the cavalry) in a snowstorm. After a conference between Paxton and the infantry's Colonel Philander P. Lane, the infantry aborted their mission and began a return to camp. Paxton also considered aborting the mission, but was persuaded by Powell to continue. Paxton sent Powell and 2nd Lieutenant Jeremiah Davidson with 20 men from Company G down the mountain to scout for the rebel camps.