DeBary is a city in Volusia County, Florida, United States, on the eastern shore of the St. Johns River near Lake Monroe.

In 1866, Elijah Watson of Enterprise sold land to Oliver and Amanda Arnett on the northern shore of the St. Johns River at Lake Monroe, where they built a house.

The couple in turn sold 400 acres (1.6 km2) in 1871 to (Samuel) Frederick deBary, a wealthy wine merchant from New York City, and that same year, he erected a hunting lodge.

Called "DeBary Hall", the 8,000-sq-ft (700-m2), 20-room Italianate mansion featured a two-tiered veranda, stables, an ice house, and the state's first swimming pool, fed by a spring.

One possibility is that this was the first spring-fed pool in the state, In 1875, deBary bought a small steamboat, the George M. Bird, to transport his horses and dogs along the St. Johns River for hunting expeditions, and also to take fruit to market.

He established the DeBary Merchants' Line in 1876, a steamship service contracted to carry mail between Jacksonville and Enterprise.

Frederick deBary died in 1898, and his mansion is today a restored museum, listed on the National Register of Historic Places in 1972.