Fifty years ago this week, Britain went to the polls amidst simmering tensions over race, immigration and our place in the world. Fought in the aftermath of a tumultuous Parliament – where Labour had grappled with divisive legislation such as the Commonwealth Immigrants Act and the Race Relations Act – the National Front was thought to be on the rise, promising to make Britain great again by stopping immigration and starting repatriation.

As a mini culture war developed, “Marxist” students were condemned for sabotaging Conservative meetings across the country, while dockworkers marched in support of the country’s most well-known politician – Mr Enoch Powell. Powell warned Britons of a potential Civil War of “American dimension”, of “division, violence and bloodshed” if immigration was not halted.

In the Summer of 1970 – as Britain sweltered in a heatwave of general election and World Cup fever – one man sought to change public attitudes. Dr David Pitt – a name now lost in the passages of time – attracted worldwide attention as Labour’s only black parliamentary candidate. Fighting the Labour seat of Clapham – and with the party expected to be re-elected nationally with a sizeable majority – the Washington Post anticipated he was about to become “the first black member, 101 years after the United States” had done the same.

Dr Pitt – who came to Britain from Grenada to study medicine in the 1930s – was a prominent champion of immigration and minority ethnic rights at a time of dangerous hostility to the cause. Pitt went toe to toe with Oswald Mosley and the “White Defence League” in 1950s Notting Hill, demanding that legislation be made to make “incitement to racial hatred illegal”. He espoused radical solutions to avert tensions – such as police forces recruiting more black officers.

Pitt believed that Parliament was the best route to achieve social change. In 1959 he made history – as the first person of African descent to stand for Parliament – for Labour in Hampstead. Moseley supporters disrupted meetings and heckled him with their slogan of “Keep Britain White”. Fights broke out and Pitt was forced to seek police support after death threats and a barrage of abusive “go home Nigger” phone calls were made and he subsequently failed to take the seat.

His relationship with the Labour Party, however, was at times an uneasy one. He emerged as one of the most high profile critics of Harold Wilson’s immigration policies, attacking what he saw as cowardice in Labour’s ranks: “nobody in authority has the courage to tell the immigrant what his contribution is to the economic life of the country”. He once admitted to that “the leadership are not really sure what to do about me” as they “have always been afraid of appearing too black”.

W­hen he won the nomination for Clapham in 1970 – beating twelve white candidates – commentators remarked that the stars could align in a constituency where William Wilberforce had organised his campaign to abolish slavery.

Pitt decided to stick to “conventional Labour issues” such as poor transport and the health service. Fears of bloodshed were soon quashed as the Conservative candidate opted to avoid the issue of race and the National Front devoted its energy to other seats. The Times was confident that “his record lends support to the idea that he is being accepted in Clapham as a Labour man rather than a black man”.

Enoch Powell, on the other hand, hit the headlines with a personal address to “halt immigration now”, and policies that newspapers were keen to point out would have prevented Pitt from ever reaching British shores. Wilson and Heath opted not to engage with Powell – who was seen as a threat to both parties.

Tony Benn – showing early signs of a deviation from the party line – mobilised the Labour left with an emotive attack on Powell. In the most infamous moment of the campaign, he warned that the flag hoisted at Wolverhampton (Powell’s constituency) “is beginning to look like the one that fluttered over Dachau and Belsen”.

Benn’s comparison to concentration camps came at a time when memories of war underpinned the national story. It caused outrage in the media, so much so that the Daily Mirror warned readers that they may not be able “to stomach” the reprinted speech in their edition the next day. Benn’s diaries later revealed the extent of Wilson’s anger: “Harold is furious about it and has left a message for me to keep off the racial question”.

Nobody in authority has the courage to tell the immigrant what his contribution is to the economic life of the country

As the campaign came to a climax, commentators began to report on some resistance in Clapham. The Guardian quoted a Battersea power worker who said 65% of his workers “agree with Mr Powell” and that having “fought for England I think it should be a white man that does this job”. Labour’s Tribune, recounted anecdotes of activists being met by chants of “Enoch, Enoch, Enoch” and reports that Labour voters would not be turning out.

As the heatwave subsided, Wilson’s poll lead began to look shaky. His confident campaign was hit by a double whammy of a negative balance of trade figures and a national tragedy in England’s exit from the World Cup. On election night, it soon became clear that the pollsters had got the mood of the country wrong as Heath put the Conservatives back in Downing Street. In Clapham, Pitt suffered a major swing against him of 10.2%, double that of neighbouring constituencies and the national average. The Labour vote share was down 11%.

Pitt made his way to the BBC election night studio to answer Robin Day’s question:  “do you attribute it to colour prejudice?” Amicably, he claimed that it was probably because “people hadn’t had the chance to get to know me”. “Race played only a small part in my defeat” he later wrote “and we will be doing the community a grave disservice if we rated it any higher.”

Labour activists were more sceptical. In the days following the result, a leaflet was unearthed by the South London Press which had been sent to “electors who have coloured families as neighbours” by an unknown protest group. It was reprinted in full, reading “If you want a coloured for a neighbour, vote Labour. If you’re already burdened with one, vote Conservative”. Underneath it urged voters to support the Tories to bring up to date the “Ministry of Repatriation”.

The origin of the leaflet, and its ultimate effect on the campaign, are still unknown. In the end, Labour opted not to pursue the matter further with Pitt reaffirming that it was not a Conservative sanctioned leaflet. Many suspected it was the work of the National Front, but a spokesman dismissed such claims, because “our name is always proudly printed on our propaganda”.

The loss meant that Pitt never stood in another general election. And although he enjoyed a stellar career later as chair of the GLC, president of the British Medical Association and as Lord Pitt of Hampstead, his name is now largely forgotten. Instead the names of Bernie Grant, Diane Abbott and Paul Boateng – who achieved the historic electoral feat of becoming the first black MPs seventeen years later – will live on over time.

But as Britain begins to re-visit the people and the stories so often overlooked, Dr David Pitt’s campaign serves as a reminder that it is not just the winners who should underpin our national story.