The school opened in 1954, which makes it the oldest operating high school in Loudoun County.
Mascot The previous mascot for the school, the Raider, was named after the
Mosby's Raiders. The mascot was chosen by a segregated student body in 1954. The original school seal depicted the Raider on horseback with a
Confederate Battleflag in his hands. This logo was changed to the current design in response to criticism over the emblem. Previous attempts to remove the mascot were made in the 1970s and 1990s. Amid the
George Floyd protests in 2020, alumni started a petition to change the mascot. The new mascot, the Captains, was adopted on September 2, 2020.
Murals In 1957 murals that illustrate important events and times in Loudoun County's history were painted in the Auditorium by the Loudoun Sketch Club. Two subsequent murals were created, one in the 1970s, the other in 2004 (commemorating the school's fiftieth year in operation).
Renovations County has undergone several renovations and expansions since it was opened. The first expansion occurred in 1966, with the addition of a Vocational Education Wing attached to the side of the front portion of the building (Vocational Education has since moved to
C.S. Monroe Technology Center). In 2002, two high school seniors set an assistant principal's office on fire, closing school for a week. Because of the fire's damage, the school had to replace its old-fashioned bell system with an electronic one that the other five high schools at that time used. The main office was renovated before the end of the 2001–2002 school year.
Segregation County originally opened up as a segregated school for whites. Black students went to
Douglass High School. In the 1968–1969 school year, County became fully integrated. == NJROTC ==