Historian Tristram Hunt tells a tale of two cities.
In the 1860s, the great port of Liverpool and the industrial powerhouse that was Manchester and its surrounding towns were both deeply involved with America and its great export industry: cotton.
But when the American Civil War erupted in 1861, it began to pull the two cities in very different directions.
Tristram begins at the house of Charles Kuhn Prioleau, a South Carolina cotton trader who set up home in Liverpool.
Prioleau took it upon himself to start privately - and illicitly - funding a fleet of deadly warships for his embattled Confederate homeland.
Merseyside shipbuilder Laird's was happy to help.
What's more, under Abraham Lincoln, the American North blockaded the South and stopped it exporting cotton.
Tristram hears how this angered many Liverpool businessmen, who began to back the Confederacy, helping to smuggle supplies through the North's blockade.
There was even a Bazaar at Liverpool's palatial new St George's Hall, to raise money for the Confederate prisoners.
Meanwhile, the choking-off of cotton supplies from the American South had a terrible impact on the mill-workers of Lancashire, who suddenly found themselves out of work, and increasingly short of food.
This led some to hope for a swift end to the war.
And yet, even in the throes of 'Cotton Famine', many cotton workers gathered at Manchester's Free Trade Hall and issued an extraordinary message to President Lincoln.
They assured him that, though his blockade was imposing great hardship on them, they still supported his battle against slavery.
And this extraordinary gesture led not just to a grateful response from Lincoln, but a rich political reward - Presenter: Tristram Hunt MP
Producer: Phil Tinline
With: Thomas Sebrell, Jerry Williams, Michael Benbough-Jackson, David Brown and Alan Kidd.
Tristram Hunt on a tale of two cities, and their contrasting response to the US Civil War.