One of the first songs I ever learned, was my home-town university's fight song:

"Oh, who owns New York?/ Oh, who owns New York?/ Oh, who owns New York, the people say... Oh, we own New York..."

There will probably come a time by the mid-21st Century when Harlem will cease to be majority black Manning Marable, Professor of African-American history, University of Columbia

According to the song, the owners were C-O-L-U-M-B-I-A... which once upon a time, before I was born, had a football team that actually won games, and dominated New York intellectual life.

The Columbia fight song unintentionally and succinctly asks a profound social question - who owns a city, or a city's neighbourhoods?

The simple answer would be those whose names are listed as owners on property deeds, but I'm talking about a more complex concept of ownership.

The question came up while in Harlem recently to make a BBC radio documentary on its gentrification and changing racial character.

Harlem is, of course, the most iconic African-American neighbourhood. The ghetto of ghettos, the well-spring of so much black culture - and for that matter American culture - that it is almost impossible to imagine it as something else.

But in the southern part of Harlem between Central Park and 125th Street, inevitably called SoHa, more and more white people are moving into the area. Many long time residents feel that their neighbourhood is being taken from them.

Great migration

First some history. One hundred years ago, Harlem, was a white neighbourhood. Most of the residents were Jewish, many of them upper middle class.

In the blocks around Mt Morris Park at the top of Fifth Avenue at 120th Street lived prominent families like the Sulzbergers, who owned The New York Times, and the Rodgers, whose composer son Richard, would be one half of two of the greatest songwriting teams in American history. His future partners, Lorenz Hart and Oscar Hammerstein II lived in the neighbourhood as well.

Further uptown, in a less well-off section of Harlem, lived another songwriting duo, George and Ira Gershwin.

That began to change during World War I and immediately afterwards, as the neighbourhood became a magnet for black people making the great migration from the South, according to Manning Marable, professor of African-American history at Columbia.

"Harlem personified opportunity and jobs," says Marable. "By 1920 the neighbourhood has roughly 80,000 African-Americans, by 1940 500,000, by 1945 700,000. So, for about 25 or 30 years Harlem becomes the largest urban black neighbourhood in the world."

During this time a cultural renaissance erupted in the black community. Music, literature and politics flourished. Harlem's iconic nature was established.

Marable points out that in a recent survey of professional historians, of the 100 most influential African Americans, 41 of them came from Harlem - what the professor calls "a slender sliver of urban America no more than three miles wide and one and a half miles north and south".

Abandonment

The decades of Renaissance were followed by decline as Harlem's middle-classes headed for the suburbs after World War II. A slow cooling off became a rapid descent in the 1960s, remembers lifelong Harlem resident, Dawn Harris Martin.

Image caption Harlem brownstones have been in great demand for a decade

Like many black Harlemites she voted for John F Kennedy, believing he would resume the progressive policies of Franklin Roosevelt's New Deal.

"I was so hopeful," she says, "and when he got assassinated, I was devastated and then when his brother got assassinated I was done. And then when they started killing Martin Luther King, Medgar Evers... It was hopeless. I remember feeling totally abandoned."

Harlem was abandoned, and in thinking about who owns this neighbourhood in New York, it is an important point.

The city's government and property speculators forgot about Harlem, but the people who lived there formed a deeper community and did not. They may not have had the money to buy properties but they felt a sense of ownership because they stuck with the place through the bad times.

And now, in a reverse of 20th Century demography, upper middle class white families are returning to Harlem and what seems unthinkable is now likely to happen, according to Professor Marable.

"There will probably come a time by the mid-21st Century when Harlem will cease to be majority black," he says.

Power base

Opinion among black Harlem-ites is divided about this.

When Michael Henry Adams came to New York from the Midwest to do graduate work at Columbia, he chose to live in Harlem because of its iconic stature and has never left.

Image caption Harlem may have been a touchstone that gave blacks confidence for political leadership

"In a place as rich as America, no-one should be forced through economics alone to leave the place where they've always lived. Yet that is what is happening," he says.

Marable, like Adams, is an immigrant to Harlem from the Midwest. He grew up with Harlem as an ideal, the capital of Black America, something more than just a place of bricks and mortar. He defends the idea of Harlem remaining a primarily black neighbourhood.

"It's something I call the paradox of integration. Ghettoisation and segregation - the isolation and exclusion of blacks created a political power base. Harlem was not just a neighbourhood but a school for civic activity," he says.

If not for the touchstone of Harlem, Marable wonders if black people would ever have gained the confidence to run a neighbourhood or politically run a city and, implicitly, run America's government.

Interestingly, as I spoke with people in Harlem I found that many who had been born there had a different view, like Dawn Harris Martin.

"We have a saying up here. Harlem is the new black... it's very exciting to live in these times. Just as I thought I would never live to see a black president, I never thought I would live to see Harlem regain its stature."

Colonisation

As I say, ownership is a complicated concept. It is bound up with subjective things like memory and personal experience.

My late father-in-law emigrated to Canada from London after the war. Shortly after my wife and I moved to London, he came for what he knew would be his last visit.

The economic and social forces that shape cities are impersonal and objective

He was in his mid-80's and went off for a nostalgia trip down the Mile End road, where he was born and spent his childhood. He came back flabbergasted.

"It's not my London," he said shaking his head in disappointment.

The street markets were still there, the area was as run-down as ever, but what he meant was there was no trace of his cockney past. There were very few white faces. It had become a neighbourhood of immigrants from Bangladesh.

In memory, he owned that territory and now it seemed to have been taken over without his permission.

I deeply empathise. My old neighbourhood in New York, Alphabet City, was a rough place with a strong community, united in poverty and powerlessness as our streets went up in flames in the 70's and early '80's and and we dodged the violent fall-out of the drug business.

In the last decade and a half it has been colonised and cleansed and made safe for upper middle class professionals and their children. I'm happy the streets are safe at last, I just wish the people who suffered when they weren't safe could still afford to live there.

Perhaps there is no satisfactory answer to the question of who really owns New York - or London - or Paris - or any world city.

The economic and social forces that shape cities are impersonal and objective, the sense of ownership is personal and subjective.

As a physical place, Harlem may not survive as a black neighbourhood, as a historical and cultural place I doubt it will ever be anything else.

Michael-Goldfarb.com

The first episode of Michael Goldfarb's radio documentary can be heard on Wednesday 2 February, on the BBC World Service.