According to chapter 1, the ancestor furthest back in Atticus' tree would be Simon Finch, who established his homestead on the banks of the Alabama River. That was where Finch's Landing began. The men in the Finch family were the ones to stay on the Landing from generation to generation. However, when Atticus was old enough, he went to law school, while his brother (Jack) attended medical school. That left Alexandra, their sister, to remain at Finch's Landing. Alexandra also had children and a grandchild named Francis. His was the only name given in the text (during the Christmas chapter 9) Also a "cousin Ike" was mentioned--he was Atticus' cousin. Those were the names that were given. The only two who would follow after Atticus in his tree would be his two children, Jem and Scout.