In the antebellum South, most cotton planters relied on cotton factors (also known as commission merchants or cotton brokers) to sell their crops for them.
This factor was usually located in an urban center of commerce, such as Charleston, Mobile, New Orleans, or Savannah (harbor cities; there was not yet a network of railroads), where they could most efficiently tend to business matters for their rural clients. Prior to the American Civil War, the states of Alabama, Georgia, Louisiana, and Mississippi were producing more than half of the world's cotton, but Arkansas, Tennessee, and Texas produced large amounts also. At the same time, the port of New Orleans exported the most cotton, followed by the port of Mobile.
Cotton factors also frequently purchased goods for their clients, and even handled shipment of those goods to the clients, among other services.
As one source notes,
The factor was a versatile man of business in an agrarian society who performed many different services for the planter in addition to selling his crops. He purchased or sold slaves for his client, arranged for the hiring of slaves or the placing of the planter's children in distant schools, gave advice concerning the condition of the market or the advisability of selling or withholding his crop, and bought for his client a large proportion of the plantation supplies.