The mouth of the bay is marked on the east by a long narrow peninsula of sand, Mobile Point, that separates Bon Secour Bay, where the Bon Secour River enters the larger bay, from the gulf.
The point ends at the main channel into Mobile Bay, and here the United States government erected a pre-war fort to shield Mobile from enemy fleets.
The war was already winding down, and assertions were made that the morale of the soldiers was bad.
Complete control of lower Mobile Bay thus passed to the Union forces.
Mobile had been the last important port on the Gulf of Mexico east of the Mississippi River remaining in Confederate possession, so its closure was the final step in completing the blockade in that region.
The bay is about 33 mi (53 km) long; the lower bay is about 23 mi (37 km) at its greatest width.
It is deep enough to accommodate ocean-going vessels in the lower half without dredging; above the mouth of Dog River the water becomes shoal, preventing deep-draft vessels from approaching the city.
Tennessee did not then retire, but engaged the entire Northern fleet.
Tennessees armor enabled her to inflict more injury than she received, but she could not overcome the imbalance in numbers.
Across the entrance, the line of the peninsula is continued in a series of barrier islands, beginning with Dauphin Among the most embarrassing episodes of the war for the U. Navy was the passage of the raider CSS Florida through the blockade into Mobile Bay on September 4, 1862; this was followed by her later escape through the same blockade on January 15, 1863. Farragut when he was assigned to command of the West Gulf Blockading Squadron had included instructions to capture Mobile as well as New Orleans, the early diversion of the squadron into the campaign for the lower Mississippi meant that the city and its harbor would not receive full attention until after the fall of Vicksburg in July 1863.
Given respite by the Union strategy, the Confederate Army improved the defenses of Mobile Bay by strengthening Fort Morgan and Fort Gaines at the entrance to the bay.
This Union victory, together with the capture of Atlanta, was extensively covered by Union newspapers and was a significant boost for Abraham Lincoln's bid for re-election three months after the battle.