At the height of World War Two, with the country gripped in a life or death fight for freedom against fascism and dictatorship, dozens of local drinkers fought alongside black soldiers against white Military Police officers harassing them outside a Lancashire pub.

It was just one extraordinary example of the active support shown by ordinary Britons for the thousands of black American troops stationed amongst them during the war - in stark contrast to the vicious racist abuse they received from their fellow countrymen.

The Lancashire riot was just one of hundreds of cases of simple humanity displayed by ordinary Britons towards black soldiers.

Details of the riot are revealed in a new book exploring the experience of black GIs stationed in Britain during the war.

“These men have been sent to this country to help in its defence, and whatever their race or creed they should be entitled to the same treatment as our own soldiers.” Letter to the Bath Chronicle and Weekly Gazette

While white GIs sought to have them banned from pubs, clubs and cinemas and frequently subjected them to physical and verbal assault, many ordinary Britons welcomed the black troops into their homes - and on several occasions physically stood up to their tormentors.

The book, Forgotten: The Untold Story of D-Day’s Black Heroes, at Home and at War, also reveals how in June 1943 there was a public outcry when four black servicemen were refused service in a bar in Bath, for no reason other than the colour of their skin.

One resident described the episode as “disgraceful” and wrote to the Bath Chronicle and Weekly Gazette stating: “These men have been sent to this country to help in its defence, and whatever their race or creed they should be entitled to the same treatment as our own soldiers.”

Photo: National Archives and Records Administration

In one of the most notorious incidents fighting broke out when white Military Police officers – one of whom was drunk - began harassing black GIs outside a pub in the Lancashire village of Bamber Bridge.

But in what could be regarded as a surprising turn of events the locals sided of the black troops.

A later account of the riot, which began on June 24, 1943, stated: “The MPs expected the locals to resent the presence of the blacks but the locals sided with the blacks. The MPs, using racial expletives, returned with two more and tried to frighten the blacks, who fought back with bricks and bottles.”

More than seven servicemen were wounded in the fighting and 32 black soldiers were later court-martialled. Between November 1943 and February 1944 there were 56 such clashes between white troops and their black counterparts, an average on more than four a week.

GI Willie Howard, of the segregated 320th Barrage Balloon Battalion - whose task on the D-Day beaches was to raise the curtain of balloons protecting Allied troops from German planes - later went as far as to say: “Our biggest enemy was our own troops.”

Photo: Linda Hervieux

In another notable case a public campaign, including a petition of thousands of British signatures, led to the US President Eisenhower revoking the death sentence on Leroy Henry, a black soldier wrongly convicted of raping a woman near Bath, in May 1944.

The book also cites a letter from the owner of a café in Oxford to the Times, in which he recalled a black soldier presenting him with a letter from his commanding officer asking him to be served.

The café owner, a Mr D. Davie-Distin, promptly served him and said: “Had there been the slightest objection from other customers I should not have had any hesitation in asking them all to leave.”

And he added that the incident had left him “ashamed” that a man “fighting for the world’s battle for freedom and equality” had to resort to such humiliating measures to obtain a meal.

For the black GIs, to be treated with basic decency, after years of suffering humiliation, abuse and the daily threat of lynching from whites in the segregated southern states of their native US was, in the words of one of their number, Arthur Guest, like “a spark of light”.

Photo: Linda Hervieux

Guest was a sergeant with the 320th Barrage Balloon Battalion – entirely composed of black soldiers led by white officers – which arrived in Pontypool, South Wales, in February 1944, and found itself among a population that had rarely seen a black face before.

“The general consensus of opinion seems to be that the only American soldiers with decent manners are the Negroes.” George Orwell

Another member of the 320th was Wilson Monk , who was billeted in the basement of the town’s Trinity Methodist church.

Here he met the organist Godfrey Prior, a milkman, who quickly invited him to join the congregation.

Photo: Courtesy of Wilson Monk

Mr Prior’s wife Jessie took it on herself to provide Monk with the occasional home cooked meal and – with her 18-year-old boy Keith away on active service - came to look on him as a surrogate son.

In February 1944 she wrote a touching letter from her home in the village of Abersychan to Monk’s mother Rosita, in Atlantic City, New Jersey, to reassure her about her son’s well-being.

Mrs Prior, who like most Britons outside of the port cities of Liverpool, Cardiff, London and Bristol, has never seen a black person before, told her:

“Mrs Monk, you have a son to treasure and feel very proud of. We have told him he can look upon our home as his home while in our country. We shall take every care of him . . . we will look upon him now as our own.”

Photo: Linda Hervieux

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The book, by US journalist Linda Hervieux, chronicles how the arrival of 130,000 black troops in Britain – in many places they were the first Americans soldiers to arrive - had presented the British authorities with a dilemma.

Although Churchill’s war Cabinet objected to their presence, British officials rejected US Army requests that the men be formally segregated from the white population, fearing a negative reaction from voters over what would be regarded as a distinctly ‘un-British’ policy.

Photo: Linda Hervieux

At a time of rising nationalist sentiment across the British Empire they were also worried about alienating Commonwealth troops if they began to treat black soldiers as second class citizens.

But anticipating a backlash from white American troops, civil servants introduced a de-facto policy of separation, designed to encourage British civilians and soldiers not to fraternise with the black GIs.

However the wider British public were far more welcoming.

“Equitable treatment abroad helped fuel the budding civil rights movement that would rock America in the coming decades.” Linda Hervieux, author of Forgotten: The Untold Story of D-Day's Black Heroes

Black troops generally behaved more courteously and with more dignity than the brash white GIs, who openly mocked Britain’s old fashioned cars, bad food and even its poor plumbing – so much so that many Britons preferred them to their countrymen, who soon earned the sobriquet of “overpaid, overfed, oversexed and over here”.

British women noted that, in contrast to the white GIs, the black soldiers did not cat call them – something that back home could have seen them lynched.

George Orwell wrote in Tribune: “The general consensus of opinion seems to be that the only American soldiers with decent manners are the Negroes.”

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The presence of so many black troops on British soil had a lasting legacy in a country that was soon to see an influx of Afro-Caribbean migrants, starting with the arrival of the Windrush ship at Tilbury, in 1948.

Photo: Courtesy of the Adkins family

While most people have heard of the GI babies the US troops left behind, few have considered that many of these children were of mixed-race, the offspring of affairs between local white women and the black soldiers they encountered.

Many of those “brown babies” only came to know their fathers in later years, with some of their descendants now embarking on a search for their American grandfathers.

Miss Hervieux said: “Given the racial tensions that exist in Britain today, as in other countries, it is hard to believe that the UK was once a relative racial paradise for African Americans. Britons were willing to open their hearts and minds to fellow human beings who were there to help them.

She added: “Their efforts extended beyond mere hospitality. True and deep friendships developed, some of which endured long after the war. Although Britons suffered through vicious bombings that ravaged the country and extreme privation, they never forgot basic human kindness.”

The treatment the men received at the hands of ordinary British men and women also had a significant impact on post-war America, believes Mrs Hervieux.

“In Britain America’s black soldiers were welcomed and treated with respect and kindness. Once they returned home, there was no going back,” she said. “Equitable treatment abroad helped fuel the budding civil rights movement that would rock America in the coming decades.”

Forgotten: The Untold Story of D-Day's Black Heroes, at Home and at War, by Linda Hervieux, is published by Harper Collins.