The West Virginia National Guard traces its heritage to the 1735 militia company established in Berkeley County by Morgan Morgan. Originally formed for protection against Indian raids, militia units were quickly mobilized when necessary in war time. Militia units provided frontier service in the French and Indian War and during Dunmore's War. Men from Western Virginia fought on all fronts in the Revolutionary War. During the War of 1812, Western Virginia militia units took part in the Northwest campaigns, and one company of Cabell County troops fought alongside Andrew Jackson at the Battle of New Orleans in 1815. Cabell, Berkeley, and Jefferson counties provided infantry regiments for service in the Mexican War of 1846-1848.

During the Civil War, West Virginia provided some 40,000 men for service in both Northern and Southern forces. Many enlisted in the regiments of bordering states, especially Kentucky, Ohio, Pennsylvania, and Virginia. These troops primarily saw service on West Virginia soil or in the Valley of Virginia. Federal and Confederate units from West Virginia were present at both the first land battle of the war at Philippi and at the Confederate surrender at Appomattox.

A few ceremonial and social militia companies were formed after the Civil War, but the state did nothing to encourage their formation. Although violence during the Railroad Strike of 1877 led industrialists to plead for more militia companies, organization of the militia continued to be slow due to a lack of popular and legislative support. However, national labor problems and the formation of the National Guard Association as a lobbying group resulted in federal legislation that furnished funding and material for Guard companies. In 1889, the West Virginia legislature renamed the militia the West Virginia National Guard and provided state support. The First Infantry Regiment was organized in northern West Virginia and the Second Infantry Regiment in southern West Virginia.

In 1898, the two regiments were merged into one for service in the Spanish-American War. The First West Virginia Volunteer Infantry was stationed in Georgia. Later, another regiment was formed, the Second West Virginia Volunteer Infantry, which served in Pennsylvania during the war.

The militia or National Guard was activated for service in areas of labor unrest in 1877, 1880, 1894, 1902, and 1912. Though there were hundreds of strikes during this period, most were controlled by local police authorities. When this failed, troops were called to duty. The most prolonged service took place in 1902 when a national coal strike brought miners out in the New River Gorge, and in 1912—13 when miners struck for union recognition on Paint and Cabin creeks in Kanawha County. Martial law was declared for the strike zone in 1912, and miners and mine guards were sentenced to prison for various violations. "Mother" Jones was among those brought before the court-martial.

In 1916, the West Virginia National Guard was activated in response to President Woodrow Wilson's call for troops to pursue Pancho Villa on the Mexican border. Again, the regiments were merged and the Second West Virginia Volunteer Infantry was sent to the border. After several months the unit returned home, only to be federalized within weeks for service in World War I. The Second Regiment and a newly recruited First Regiment were absorbed into the 38th Infantry Division. The Second Regiment was reorganized and redesignated as the 150th Infantry while the First Regiment was broken up into support units. The 150th Infantry landed in Europe at the end of the war and saw no action in that conflict.

Following World War I, the 150th and 201st Infantry Regiments were organized in southern and northern West Virginia, respectively. These units were federalized in January 1941 as President Franklin D. Roosevelt prepared the nation for war. The 150th spent World War II defending the Panama Canal while the 201st provided the first line of defense for the Aleutian Islands. The National Guard was dramatically changed after World War II. Artillery units, transportation, and engineering units were added to the 150th Infantry Regiment. Probably the biggest change, however, was the addition of a combat fighter squadron, bringing an important aviation component to the Guard.

Since World War II, the Army and Air National Guard has served in a number of capacities, lending aid to West Virginians during natural disasters caused by periodic flooding and to victims of the coal refuse dam break on Buffalo Creek in 1972. As part of its military mission, elements of the West Virginia Army and Air National Guard were activated for duty during the Korean War, the war in Vietnam, the Gulf War of 1991, the Iraq War, in support of the peacekeeping mission to Bosnia in 1997—98, and more recent conflicts in Iraq and Afghanistan.

The West Virginia National Guard was mobilized more frequently after the attack on the World Trade Center on September 11, 2001, than at any other time in its history. Elements of the West Virginia Army and Air National Guard served in action in Afghanistan and in Iraq.