The island remained under-developed until a brief boom of economic activity during the American Civil War, when it was a center for blockade runners smuggling goods (mostly weaponry, sugar and cotton) to the Confederacy.
A illa permaneceu pouco desenvolvida ata o boom económico provocado pola Guerra Civil Americana, cando se converteu en base de operacións para os contrabandistas (sobre todo armas, azucre e algodón) dos Estados Confederados.