A brief history of the regiment:
The unit was formed Feb 1862 and by May of that year was stationed at Camp Kirkpatrick, which was located in DeKalb County, just off the Georgia Railroad - 2 miles west of Decatur and 4 miles east of Atlanta. This is where my g-g-grandfather enlisted. Initially the Battalion was made up of 5 companies A - E. Company A mustered 27 Feb, Co. B (Buckhead Artillery) - 4 March, Co. C (Columbus Rebels Artillery) - 1 April, Co. D (Gwinnett Artillery) - approx 23 April and Co. E (Wyly's Battery) - 15 May.
They were all in Atlanta until 1 July 1862, and then were sent to join Humphry Marshall's command where they saw action in SW Virginia and the Knoxville Campaign.
Company A was detached for duty at Cumberland Gap and the entire company was either killed or captured when the Gap was surrendered. The POWs were sent to Camp Douglas in Chicago. Several members of Co. A died while at Douglas and are buried at Oak Woods Cemetery in Chicago.
I don't know what became of Company B. I am thinking they were lost at the Gap as well, but I haven't seen anything that confirms that feeling.
Companies C - E left Knoxville on 23 August 1863. Arrived at Loudon on 25 August after covering 35 miles. Left Loudon on 29 August, arrived at Charleston, Tennessee on 2 September 1863 after covering 40 miles. Moved from Charleston to Ooltewah, then to Graysville, to McLemore's Cove and on to LaFayette, Georgia to join with General Braxton Bragg's forces.
As you know, the 9th fought on the left wing at Chickamauga as a part of Buckner's Corps. Company E was attached to Stewart's Division; Companies C and D were attached to Preston's.
The 9th was sent back to Virginia in 1864 and attached to the Army of N. Virginia. They were engaged at Chaffin's Bluff and Petersburg. At Appomatox they fought as an infantry unit. When they were surrendered on 9 April 1865, the entire 9th Georgia Battalion Infantry consisted of 20 soldiers - one officer and 19 men.