Assault from the Rear Marker, Fort McAllister, GA. Fort McAllister was a Confederate earthwork fortification near the mouth of the Ogeechee River in Bryan County. It played an important role in the defense of Savannah during the Civil War time Union naval blockade of the Georgia coast. Built in 1861 at Genesis Point, the fort was constructed on the plantation of Lieutenant Colonel Joseph Longworth McAllister, for whom it was named. Fort McAllister. The marker reads as follows : Dec. 1864. Fort McAllister, built 1861-62 to close the Great Ogeechee River to enemy ships, mounted 11 siege [sic] guns, 12 field pieces and 1 10-inch mortar. Below it, piles and torpedoes obstructed the channel. As the Union forces neared Savannah, the fort´s capt...