 One of the most famous naval engagements of the war was the Battle of Mobile Bay, resulting in the Union taking control of Mobile Bay on August 5, 1864.On April 12, 1865, three days after Robert E. Lee's surrender at Appomattox Courthouse, the city surrendered to the Union army to avoid destruction after Union victories at nearby Spanish Fort and Fort Blakely.On May 25, 1865, the city suffered great loss when some three hundred people died as a result of an explosion at a federal ammunition depot on Beauregard Street.