Manassas (formerly Manassas Junction) is an independent city in the Commonwealth of Virginia. As of the 2010 census, the population was 37,821. The city is surrounded by Prince William County and the independent city of Manassas Park. The Bureau of Economic Analysis combines the city of Manassas (along with Manassas Park) with Prince William County for statistical purposes.
Manassas also surrounds the county courthouse, but that county property is not part of the city. The City of Manassas has several important historic sites from the period 1850–1870.
In July 1861, the First Battle of Manassas – also known as the First Battle of Bull Run – the first major land battle of the American Civil War, was fought nearby. Manassas commemorated the 150th anniversary of the First Battle of Manassas during July 21–24, 2011.
Second Battle of Manassas (or the Second Battle of Bull Run) was fought near Manassas during August 28–30, 1862. At that time, Manassas Junction was little more than a railroad crossing, but a strategic one, with rails leading to Richmond, Virginia, Washington, D.C., and the Shenandoah Valley. Despite these two Confederate victories, Manassas Junction was in Union hands for most of the war.
Following the war, the crossroads grew into the town of Manassas, which was incorporated in 1873. In 1892, Manassas became the county seat of Prince William County, replacing Brentsville, Virginia. In 1975, Manassas became an independent city.