St. Marys is located along the southern border of Camden County at , on the north bank of the St. Marys River. The state of Florida is to the south, across the river. The city of Kingsland borders St. Marys to the west. According to the United States Census Bureau, St. Marys has a total area of, of which is land and, or 9.57%, is water. The closest major city is Jacksonville, Florida, south.
The St. Marys area was first explored in the mid 16th century as part of the settlement of Spanish Florida, with nearby St. Augustine as the established capital. Settlement for Georgians became legal after the Treaty of Paris in 1763. Local inhabitants of Camden County gathered on Cumberland Island and signed a charter for "a town on the St. Marys" on November 20, 1787. There were twenty charter members who each received four town lots and one marsh lot ; each lot was square, with the total town area being. These twenty city founders are named on an historical marker in downtown St. Marys: Isaac Wheeler, William Norris, Nathaniel Ashley, William Ashley, Lodowick Ashley, James Seagrove, James Finley, John Fleming, Robert Seagrove, Henry Osborne, Thomas Norris, Jacob Weed, John Alexander, Langley Bryant, Jonathan Bartlett, Stephen Conyers, William Keady, Prentis Gallup, Simeon Dillingham and Richard Cole. The original boundaries of the town correspond to the modern waterfront, Bartlett Street, North Street, and a block east of Norris Street. There were two public town squares. However, in the original deed the town was unnamed, and for several years afterwards in public documents it was referred to as either St. Marys or St. Patrick's, and colloquially as simply "the New Town". Accounts differ regarding the origin of the name itself—some say it is named after the St. Marys River, while others say it comes from a seventeenth-century Spanish mission, Santa Maria, on nearby Amelia Island, Florida. St. Marys was recognized by an act of the Georgia legislature on December 5, 1792, with the result of incorporation in November 1802. Oak Grove Cemetery is included in the St. Marys Historic District and was laid outside the western border of St. Marys during its founding in 1787. On June 29, 1796, the Treaty of Colerain was signed just up the river from St Marys between the United States and the Creek Nation. St. Marys town founder Langley Bryant served as the official interpreter between the Creek Indians and the United States. St. Marys was made a United States port of entry by act of the U.S. Congress March 2, 1799. The first Collector was James Seagrove. During the antebellum period, Archibald Clark served as the U.S. Customs Collector from 1807 until his death in 1848. After the Act Prohibiting Importation of Slaves took effect in 1808, St. Marys became, along with Spanish Amelia Island, a center for smuggling, especially during the period between 1812-1819 when various rebel groups held Amelia Island. During the War of 1812 the Battle of Fort Peter occurred near the town, at the fort on Point Peter along the St. Marys River. The British captured the fort and the town and occupied it for about a month. The United States Navybombarded the town's shoreside buildings during the American Civil War. St. Marys served as Camden County's seat of government from 1869 until 1923.
Demographics
As of the census of 2000, there were 13,761 people, 4,837 households, and 3,758 families residing in the city. The population density was 733.8 people per square mile. There were 5,351 housing units at an average density of 285.3 per square mile. The racial makeup of the city was 72.78% White, 19.99% African American, 0.47% Native American, 1.21% Asian, 0.07% Pacific Islander, 1.56% from other races, and 2.09% from two or more races. Hispanic or Latino people of any race were 4.46% of the population. There were 4,837 households out of which 47.8% had children under the age of 18 living with them, 59.8% were married couples living together, 14.2% had a female householder with no husband present, and 22.3% were non-families. 16.8% of all households were made up of individuals and 2.9% had someone living alone who was 65 years of age or older. The average household size was 2.83 and the average family size was 3.18. In the city, the population was spread out with 33.4% under the age of 18, 11.2% from 18 to 24, 34.7% from 25 to 44, 15.6% from 45 to 64, and 5.2% who were 65 years of age or older. The median age was 28 years. For every 100 females, there were 97.8 males. For every 100 females age 18 and over, there were 95.3 males. The median income for a household in the city was $42,087, and the median income for a family was $46,065. Males had a median income of $35,419 versus $24,449 for females. The per capita income for the city was $18,099. About 9.6% of families and 11.2% of the population were below the poverty line, including 14.5% of those under age 18 and 7.1% of those age 65 or over.
