In an effort to help the public understand the history of the National Guard, a historical sketch of both the National Guard of the United States and the Delaware National Guard is provided. Topics include overall history of the Guard, colonial origins, the Revolutionary War, Civil War, WWI, WWII, Korea, Cold War, Desert Storm and the Delaware Guard as it presently stands.

The National Guard is the oldest military organization in the United States whose lineage of 357 years of service can be traced back to four units in Massachusetts. The 181st Infantry, 182nd Infantry, 101st Field Artillery and the 101st Engineer Battalion have the oldest lineage in the National Guard and the U.S. Army. They were organized on December 13, 1636 when the General Court of the Massachusetts Bay Colony ordered the organization of the colony's military companies into three regiments, the North, South and East Regiments. The colonists had adopted the English militia system which obligated all males, between the ages of 16 and 60, to possess arms and participate in the defense of the community. The early colonial militia drilled once a week and provided guard details each evening to sound the alarm in case of attack. The growing threat of Pequot Indians to the colony required the militia to be at a high state of readiness.

The Marquis de Lafayette, who commanded a Virginia brigade during America's War of Independence, coined the phrase "Garde Nationale" for his French Revolutionary Army during the French Revolution in the 1790's. Lafayette popularized the term in the United States, during a return visit in 1824, by applying it to all organized militia units in America. The term immediately began to appear in newspapers and magazines as popular slang for the militia.

The 2nd Battalion, 11th Regiment of Artillery, New York Militia, voted to rename itself the "Battalion of National Guards" in 1824 in tribute to Lafayette's command of the Paris militia. New York, by state statute, adopted the term National Guard for its militia during the Civil War. Many states followed New York's lead after the Civil War by renaming their militias "National Guard." The term was not recognized as the militia's formal title by federal legislation until the 1916 National Defense Act.