I could not find any record prior to 1860, but did find this which might be him:

1860 U.S. Federal Census - Slave Schedules results for John R Hartt

Age Gender Race Name of Slave Owner Home in 1860

60 Male Black John R Hart North Carolina, Floyd, Georgia
38 Female Black John R Hart North Carolina, Floyd, Georgia
35 Female Black John R Hart North Carolina, Floyd, Georgia
28 Male Mulatto John R Hart North Carolina, Floyd, Georgia
15 Male Black John R Hart North Carolina, Floyd, Georgia
15 Female Black John R Hart North Carolina, Floyd, Georgia
12 Female Black John R Hart North Carolina, Floyd, Georgia
7 Male Black John R Hart North Carolina, Floyd, Georgia
2 Female Black John R Hart North Carolina, Floyd, Georgia