At the time of the 1860 U.S. census of New Orleans, Wilson had the second-highest net worth of the 34 residents who listed their occupation as "slave trader".

[6] Historian Alexandra J. Finley describes Barnett as a "go-to notary for slave traders" who worked at one time as an agent for Wilson.

[7] In 1849 J. M. Wilson (as he usually styled himself in print) became head of his own business, located on Camden Avenue near Light Street in Baltimore.

[3] According to Frederic Bancroft, from his beginnings as an traveling agent Wilson rose through the ranks of the Upper South's enslavement-business community and eventually became a slave trader "of the first class" and among the "best known resident traders" of 1850s Baltimore, along with John N. Denning, Bernard M. Campbell & Walter L. Campbell, and Joseph S.

'"[11] In 1852 a slave buyer used Louisiana's redhibition laws to demand a refund for an enslaved woman who had been "warranted sound" but died of incurable consumption shortly after he bought her from J. M.

[7] The Natchez Trace collection at the University of Texas includes "a pre-printed slave bill of sale for 13 young women, aged 14–20, all having last names, including Queen Barksdale (age 15), sold as a group for $16,000 to planter Benjamin Roach by slave-trader J. M. Wilson.

[14] Meanwhile, in Baltimore, Wilson & Hindes offered a $200 reward for the recapture of 20-year-old Oscar Henderson, described as a "bright mulatto, gray eyes and slightly pock marked, about 5 feet 8 or 9 inches high, rather thin visage and slender form".

[15] There were multiple instances in the 1850s of lawyers getting writs of habeas corpus for people being held in the Wilson & Hindes slave jail in Baltimore, people whom the lawyers claimed were legally free: one such case was a boy named James Johnson in 1857 who may or may not have been sold by his own father, who still held title to his mother.

[7][a] In October 1860 William H. Nabb was working as a trading agent for Wilson & Hindes, based out of the Union Hotel in Easton, Maryland.

[27][28][29] In 1854, businessman and slave trader Joseph S. Donovan hired Moses Hindes as the bricklayer for his construction of four large warehouses at the corner of Camden and Charles.

"[33] Slave traders often provided new outfits of clothes for their prisoners,[8] in order to increase their appeal to potential buyers (the Duke Street slave jail complex in Alexandria even had its own tailor shop),[34] and it is possible that the stolen clothes and shoes may have been stockpiled in Wilson & Hindes' jail for this purpose.