Jacksonville is a city in Onslow County, North Carolina, United States. As of the 2010 United States census, the population was 70,145, which makes Jacksonville the 14th-largest city in North Carolina. Jacksonville is the principal city of Onslow County and is included in the Jacksonville, North Carolina metropolitan area. In 2014, Forbes magazine ranked Jacksonville as the fifth-fastest growing small city in the United States. Demographically, Jacksonville is the youngest city in the United States, with an average age of 22.8 years old, which can be attributed to the large military presence. The low age may also be in part due to the population drastically going up over the past 80 years, from 783 in the 1930 census to 70,145 in the 2010 census.
It is the county seat of Onslow County, and the home of the United States Marine Corps' Camp Lejeune and New River Air Station. Jacksonville is located adjacent to North Carolina's Crystal Coast area.
On 21 June 2016, the City of Jacksonville, became the first jurisdiction to adopt a paid holiday honoring the 13th Amendment to the United States Constitution, which made slavery in the United States and its territories illegal. The resolution of adoption targets the prevention of the modern slavery epidemic in the form of human trafficking, which includes forcing children to engage in labor and combat.
In recognition of the history of African Americans (and remembering the Montford Point Marines who faced second-class citizenship), Jacksonville honored their heritage and the enfranchisement their ancestors received from the 13th Amendment. The holiday (Freedom Day) will be celebrated on the second Monday in December, which will always fall between the dates of the states' ratification (6 December 1865) and Secretary of State's proclamation of the 13th Amendment to the U.S. Constitution (18 December 1865).