The history of Kennesaw dates back to the 1830s when the Georgia Legislature authorized the construction of a rail line through Cobb County. Known as the Western and Atlantic Railroad, 20 miles of track was in operation from Terminus (Atlanta) to Cartersville by 1846. Several small towns were founded along the railroad including Vinings, Smyrna, Acworth and Big Shanty.
The abundance of water and high ground adjacent to the railroad led to the construction of worker's shanties near the present day Kennesaw. This area became known as the "big grade to the shanties” and was later shortened to "Big Shanty Grade”. The high point of the railroad between the Chattahoochee and Etowah Rivers is the present day crossing in Kennesaw. In the late 1850s, a plot of land was acquired by the Railroad "for the purpose of erecting a Depot and an eating house for the convenience of the traveling public." This eating place became the famous Lacy House and was operated by Mr. and Mrs. George Lacy.
In 1861, Camp McDonald, a training camp for soldiers, was established near Big Shanty. Named for former Governor Charles C. McDonald, a resident of Marietta, Big Shanty was an ideal location for a training camp. There was fresh water available and the railroad furnished a convenient mode of transportation for recruits and supplies. There were no permanent structures, and the men lived in tents. General William Phillips of the Georgia Militia was the commander of the camp. The parade ground was located approximately where Highway 41 crosses Kennesaw Due West Road. On July 31, 1861 a Grand Review of the troops was held in the town and attracted a very large crowd. Such a crowd would not gather again until one hundred years later when The General returned to Kennesaw.