The Civil War decimated the tourist industry and local economy at Ocean Springs. Many of the local men joined the Live Oak Rifles, Company A, 3rd Mississippi Regiment which had been formed in west Jackson County in the spring of 1861. Some families moved north of the coast to farm. Those who stayed subsisted on seafood. In a letter, which survives from the period, a person living here in 1864 wrote: We are well and get along pretty smoothly. Bread stuffs are high, corn $12 to $14 per bushel, but then contra, we have fish and oysters for the trouble of catching and fruit in abundance. Chickens and eggs we raise and if hard pressed go out and shoot a rabbit.
In 1862, the Union Navy sent a detachment of sailors and marines from the USS Hartford to Ocean Springs. They went to the former U.S. Post Office on Jackson Avenue and confiscated the letter balance from John Egan's post office as well as New Orleans newspapers and dilapidated guns, rifles, and muskets.