Jacksonville is a city in Jackson County, Oregon, United States, a few miles west of Medford. It was named for Jackson Creek, which runs through the community and was the site of one of the first placer gold claims in the area. It includes Jacksonville Historic District which was designated a U.S. National Historic Landmark in 1966. As of the 2000 census, the city population was 2,235. As of July 1, 2009, the city's population was estimated to be 2,665.
Jacksonville was founded following discovery of gold deposits in 1851–1852. With the creation of Jackson County, it became the county seat, a role which was transferred to nearby Medford in 1927.
Jacksonville was home to the first Chinatown in Oregon, founded by immigrants from San Francisco, California. Evidence of this chapter of history was uncovered early in March 2004 when road work uncovered artifacts dating to the 1850s and 1860s. Construction was halted while archeologists performed four days of rescue excavations. Their findings included broken Chinese bowls and tea cups, handmade bottles, and fragments of opium paraphernalia and Chinese coins.