John A. Long was the son of John Long 11 and Elizabeth 'Smelcer' Long. He was the grandson of Rev. George W. Long 1 and Nancy Elizabeth 'Maples' Long. Also Adam Smelcer and Leah 'Ealy' Smelcer.
He was married to Mary L. Newton in Walker Co., Georgia. They were married on March 8, 1866. Mary Newton was the daughter of Reverend William Newton, who had lived in McMinn Co., Tennessee. John was a member of the Baptist Church.
John was the father of 11 children: Sarah Elizabeth James Monroe William L. Martha Lavina Thomas Walter Leona Cora Charles John Bertie Leonard R. Leonora R.