Which fort guarded Mobile Bay during two War of 1812 battles?

The fort that guarded Mobile Bay during two War of 1812 battles was Fort Bowyer.

The United States built Fort Bowyer in 1813 on Mobile Point, near the entrance to Mobile Bay, after American forces seized Mobile from Spanish control. Made chiefly of earth, sand, and timber, it protected the approaches to the port and was named for Colonel John Bowyer, who supervised its construction.

The British attacked first on September 15, 1814, using warships and troops. The fort’s American garrison repulsed the assault, and the British loss of HMS Hermes helped end that attempt. After the British defeat at New Orleans, they returned in February 1815 and captured Fort Bowyer following a short siege. News of the Treaty of Ghent soon arrived, and the British eventually returned the fort.

A common mix-up is Fort Morgan, the stronger masonry fort later built on the same strategic site. Fort Morgan became famous during the Civil War, but Fort Bowyer was the War of 1812 installation involved in both battles.