By contrast, the blockade of Wilmington was fairly conventional, and is the focus of most debate concerning the efficacy of the blockade. After the middle of July 1863, when Charleston was largely sealed off, most of the trade between the Confederacy and northern Europe was conducted through Wilmington. The port retained its primacy until near the end of the Rebellion, when Fort Fisher, at the mouth of the Cape Fear River, was captured by Union forces in January 1865.