Interesting az,

No doubt all that cotton was picked by American slaves, as abolition would have followed later after the civil war.

"The first American cotton was unloaded in Liverpool in 1784. There were only eight bags. Less than forty years later, half a million bales were arriving each year from America. Other countries also supplied cotton, including Brazil, Egypt and India. By 1850, cotton accounted for almost half of the city’s trade. Over 1.5 million bales were imported" Source.