Final answer:
The price of cotton dropped after 1865 due to a lack of supply during the American Civil War an increase in cotton production and global overproduction.
Step-by-step explanation:
The price of cotton dropped after 1865 due to several factors. Firstly, during the American Civil War, the Southern cotton planters could not sell their cotton to the North or overseas, leading to a lack of supply. This forced overseas buyers, such as those in England, to look elsewhere for cotton. By the time the war was over, the damage was done, and cotton prices fell. Additionally, the increase in cotton production and global overproduction caused a decrease in cotton prices. The expansion of cotton production in the Old Southwest and the availability of Eli Whitney's cotton gin made it possible to produce large quantities of cotton, leading to a surplus in the market and a decrease in prices.