In 1863, The US President wrote to the 'working men of Manchester' thanking them for their anti-slavery stance

When cotton was king, Manchester's busy textile mills dressed the world. Because of this, great fortunes were made and ordinary families were fed. But in 1862, Lancashire mill workers, at great personal sacrifice, took a principled stand by refusing to touch raw cotton picked by US slaves.

On the other side of the Atlantic, President Lincoln's Northern Union was waging war against a breakaway of southern states. Having already linked the south with the institution of slavery, Lincoln persuaded European importers that his blockade of slave picked cotton was a legitimate tool in defeating the Confederacy and restoring the union.

A year into the civil war, the effects of the cotton embargo really began to bite. Lancashire, which had imported three quarters of all cotton grown on southern plantations (1.3 billion lbs), found that 60% of it spindles and looms lay idle, leaving many out of work, thanks mainly to the blockade.

Whilst the British government loosely supported Lincoln, many mill and shipping companies wanted the Royal Navy to smash the blockade, allowing the precious cotton back into Europe. In Liverpool, a city made wealthy by cotton imports, it was said that there were more Confederate flags flying along the banks of the Mersey than in Virginia.

With the 'cotton famine' now taking a firm grip even the Manchester Guardian instructed the mill hands that they were better off dropping their support for the embargo. However, at a noisy meeting at the Manchester Free Trade Hall in 1862, in a historic show of solidarity against slavery, the workers agreed to keep supporting Lincoln's embargo.

Manchester Guardian, 31 December 1862. Read the full article.

Although an extraordinary gesture, the vote would be costly to the mill workers as more of them faced starvation and destitution. Disorder had already broken out in some northern towns, with the army having to read out the Riot Act.

With the cotton industry on its knees, Lincoln acknowledged the self-sacrifice of the 'working men of Manchester' in a letter he sent them in 1863. Lincoln's words - later inscribed on the pedestal of his statue that can still be found in Lincoln Square, Manchester - praised the workers for their selfless act of "sublime Christian heroism, which has not been surpassed in any age or in any country."

These words were followed by the arrival of US relief ships packed with provisions sent by grateful Americans as an act of brotherhood between the Union states and Lancashire.

In January 1865 - only a matter of months before Lincoln was assassinated by John Wilkes Booth - Congress passed the Thirteenth Amendment, which abolished slavery throughout the United States. Just as the US Constitution was being rewritten, the Confederate states, already stricken by the embargo, were being defeated by Union forces. By the time the South surrendered, Manchester had dusted down its disused mills and workshops so it could begin the difficult task of recapturing its lost industrial might.