Mobile Bay
After taking New Orleans, Farragut was promoted to rear admiral, a newly created rank. This made him the first American to become an admiral and the Navy's most senior officer. He focused on fighting the Confederate Navy in the Mississippi for two years. However, the South continued resisting the North despite Union victories on the Mississippi. The North had to take the last Confederate stronghold on the gulf, Mobile Bay.
Mobile Bay was heavily defended by Fort Morgan, a fleet of confederate ships, and a massive ironclad ship, the Tennessee. Farragut attacked with a fleet of his own and 4 smaller ironclads on August 5, 1864.
However, the massive ironclad was not the only formidable Confederate defense. Rows of torpedoes (the technology to propel them had not been invented) hung in the water like mines. One Union ironclad, the Tecumseh, sank after hitting the barrier. The other ships stopped when they saw this. Farragut would not be discouraged. "Damn the torpedoes! Full speed ahead!" he ordered. The fleet continued, and somehow avoided further damage from torpedoes. When the fleet made it past the fort, the Tennessee came after it. After an hour of battering, the ironclad surrendered. Mobile Bay belonged to the Union. All that remained was for General Grant to win his land battles and end the Civil War.