By 1830 he moved to Natchez, Mississippi, to raise sugar.
[1] From 1852–1861 he had a practice of law in New Orleans, Louisiana, in partnership with Judah P. Benjamin, later a cabinet officer of the Confederate States of America and then a successful attorney in England.
[2] Sparks published his autobiographical "The Memories of Fifty Years" in 1870.
The work consists of a wide variety of observations Sparks kept note of during his lifetime.
Sparks died in Marietta, Georgia, on January 13, 1882.