The Georgia 28th Artillery Battalion was organized at Savannah, Georgia, during the summer of 1863 with nine companies, later reduced to seven. All of its companies had seen prior heavy artillery service. It was assigned to the Department of South Carolina, Georgia, and Florida, and took an active part in the fight at Olustee.
During the Olustee Campaign the Twenty-eighth Battalion,Georgia served as infantry under the command of Major A. Bonaud. A detachment from the Florida Camp of Instruction, the Florida Conscript Company, was attached to the battalion at Olustee, and there is a slight possibility that part of the Second Florida Battalion was as well.
The battalion had been formed at Savannah in 1863 by uniting a number of independent heavy artillery companies. Olustee was the first major engagement for the unit. Comparatively small in numbers, the unit suffered over 100 casualties: 12 killed, among them Jesse Mott, 95 wounded, and two missing. The Florida Conscript Company suffered losses of six killed or died of wounds, and nine wounded. It is unclear if these loses were included in the totals for Bonaud's Battalion.
In the spring of 1864 the unit was sent north as infantry. Companies F and H were assigned to Finegan's Brigade, Army of Northern Virginia, and five companies to Elliot's, then J.C. Fiser's Brigade, Army of Tennessee. Companies F and H were involved in the Petersburg siege south of the James River and the Appomattox Campaign and surrendered with no officers and 7 men. The other five companies served at Savannah and in the North Carolina Campaign. They surrendered on April 26, 1865. Major A. Bonaud was in command.