You may think you don’t know Emory Douglas but you do: you know him through his iconic images which documented one of the most turbulent periods in black American history – the fist raised in the black power salute, the gun-toting brothers and sisters of black resistance, the slavering, fly-ridden pigs and rats of white US imperialism. Surviving on scraps of paper, flyers, posters and newspaper cuttings, an extraordinary body of work has been assembled for its British debut in an exhibition at the Urbis museum in Manchester.

From 1968 to 1982 Douglas was the official artist of the Black Panther Party, militant child of America’s civil rights movement, which rejected the politics of nonviolence in favour of the right to bear arms in defence of black oppression. The FBI director J. Edgar Hoover considered the group “the single greatest threat to the internal security of the United States”. Their hero was the assassinated black civil rights leader Malcolm X, their symbol the black power salute, memorably employed on the winners’ podium by two American athletes at the Mexico Olympic Games in 1968.

It was the era of radical protest: you weren’t alive if you weren’t marching for or against something – apartheid in South Africa, nuclear disarmament, the Vietnam War – and the Panthers were a potent symbol of frontline resistance. I’m old enough to remember them – scowling Afro-glam, exciting and quite scary – but such a long way from the middle-class agitprop of British student politics, you never expected to meet one. So it’s a curious thing to be sitting across a table from Emory Douglas, sharing a bottle of Coke and flicking through brittle, yellowing copies of the Black Panther newspaper for which he was chief illustrator. Among them is a photograph of a young Douglas, arms raised high, directing a challenging stare at the police officer about to arrest him.

Forty years on, the gaze has softened, the black halo of hair is grizzled and less abundant, the smile when it comes is transforming. Now 62, Douglas is in Manchester to promote an exhibition of his work; the show has toured the US and the impressive accompanying catalogue includes essays by academics on his life and work. As so often, history comes round to honouring the rebel outcast.

His art was of its time and community: part cartoon strip, part satire, part call to arms – “a mix of expressionist agitprop and homeboy familiarity”. How does he feel about its presence in galleries and art books? “If it’s educational,” he says, “if it tells people something about that period of history, then that’s a positive thing.” It certainly does that: even if you were living at the time, it’s easy to forget the appalling inequality suffered by black Americans. Slavery might have gone but the mentality lived on and segregation was still sanctioned in some states.

Douglas was 10 years old when he took a trip to Oklahoma to visit an aunt: “We went into a café and were not allowed to sit up at the counter,” he recalls, “That made a big impression on me.” He grew up in decaying flats in the Bay area of San Francisco with his single, blind mother. He was politicised early, “just by the stuff going on around me; there were dog tags and curfews for black kids – many Bay area police were recruited from the South and they were very racist. Black people were not allowed to work in the big chain hotels.”

He was, he says, incorrigible as a youngster: “I was into what you might call illegitimate activities; things not sanctioned by the state.” By 15 he was in a youth detention centre. There he began painting and an officer suggested he should apply to do art at city college on release.

He was also taking a keen interest in television news: “I saw reports of apartheid in South Africa – police using tanks, dogs, water hoses; then there were the student protests in South America and the viciousness of the police. Here in California whenever a black man was killed by police, it was always justified, even if he was shot in the back.

“I started going out to San Francisco State University to black student union meetings: there was Stokely Carmichael, Leroy Jones, Marvin X and other playwrights and poets.” He attended a community event where the recently formed Black Panthers were providing the armed security. “I was impressed they believed in self-defence – that there were people who didn’t want to turn the other cheek; seemed like we’d been doing that for too long.”

Two young black activists, Huey Newton and Bobby Seale, had formed the Panther Party in 1966 with the aim of protecting black community from police brutality; Douglas hooked up with them two years later. “I used to go by Bobby Seale’s house, that’s where I met the first cadre: there’d be Eldridge [Cleaver, the playwright] upstairs, Marvin [X, poet and playwright] downstairs, Bobby working on the first issue of the newspaper.” Douglas offered to help and went home for art materials. “When I got back they said, ‘You seem like you’re committed, we’d like you to be the artist.’ ”

Douglas’s work was vital in reaching a semi-literate community: “People saw themselves in my pictures,” he says. “They were the heroes – the aunties and uncles, brothers and sisters – the pictures captivated them, then they could dwell on the message.” He drew mothers sitting in rat-infested tenement rooms, a baby in one arm, rifle in the other; he drew politicians strung up in trees by their necks and posters exhorting blacks to “Shoot to kill”.

But though the Panthers were principally known – and feared – for their militant “witnessing” of illegal police raids and arrests, they also ran social programmes for housing, education and health: a poignant Douglas drawing shows a mother and child reading a pamphlet on sickle cell anaemia – a disease affecting mainly black people.

The heavy black lines and patterns in his work allude to traditional African art – a black mama boogies with raised arms under the legend, “Hallelujah! The might and the power of the people is beginning to show.”

The Panthers lived in collectives, bought property and funded their social programmes with donations from liberal supporters: Did he marry? “Well, yes and no. I was a playboy, I guess. When the party be gan the women were lookin’ good, the men were lookin’ good . . . I did marry, but my wife left the party and I had a son with another lady. Then she left and I had a kid with a new young lady.”

There was chauvinism, he says, but the Panthers had women involved in all aspects of their work. The Panthers petered out towards the end of the Seventies with leaders jailed and riven by factions. Douglas went to work for the Sun-Reporter – “a news journal for the cause of the people” – but nothing since has matched the glory days. Is the community less cohesive now? How does he feel about the misogynist violence of some hip-hop? “I’m opposed to those negative aspects,” he says, “But there’s a whole movement out there of young activists challenging it: it’s a very diverse culture.”

Do black Americans get a better deal now? “You might get the illusion that things might be a little improved – there is student access but there ain’t enough jobs.” And what hopes of Barack Obama? “He’s a fresh voice,” Douglas concedes. Is he a brother? “Yeah, sure,” says Douglas, not entirely convincingly.

Douglas is off now to lunch with poet Linton Kwesi Johnson and the playwright Kwame Kwei Armah, then back to California where he’ll have more time for work since his beloved mother died earlier this year – he’s spent much of the past 15 years looking after her. I go to shake his hand but he puts his arms round me for a big hug instead. Lovely man.

Black Panther: Emory Douglas and the Art of Revolution, Urbis, Cathedral Gardens, Manchester (www.urbis.co.uk 0161-605 8200), Oct 30-Mar 2009

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