The young tearaway who's in the running to be next Pope

When Pope Benedict XVI kicks off his four-day visit to the UK with a greeting from the Queen at Holyrood House in Edinburgh on 16 September, he will be accompanied by a gaggle of cardinals known as "Princes of the Church". And, if high-level leaks are correct, among them will be a handsome, modest and very intelligent man who is a potential contender to be the next pontiff. If that were to happen Cardinal Peter Kodwo Appiah Turkson would be the first African pope for 1,500 years.

He was born in 1948 in what was then known as the Gold Coast, a British colony in West Africa. As a boy he was, like his compatriot the former United Nations secretary general Kofi Annan, a subject of the Queen's father, King George VI. Indeed, for a few years after the king's death he was her subject, but in 1957 the Gold Coast attained independence and became Ghana.

His Eminence Cardinal Turkson, the fourth of 10 children, has wasted little time in hitting the highest reaches of the Roman Catholic Church. He is 122nd in seniority among the 179 cardinals, many of whom have retired and would never be regarded as papabili (papal material). In precedence, the Ghanaian stands just a few places behind the Archbishop of St Andrews and Edinburgh, Keith O'Brien, and the semi-retired former archbishop of Westminster, Cormac Murphy-O'Connor.

Although bookmakers have made Nigeria's Cardinal Francis Arinze the favourite to succeed Pope Benedict – and thus become the first African pope since the death of Pope Gelasius in 496 – Arinze is now 77 and retired and he may well be too old by the time of any vacancy at the Vatican.

Never seen as an ambitious cleric, Cardinal Turkson, when asked if a black man should become pope, replied with a laconic "Why not?"

Though much ancient flummery has been hacked away from today's papal court, Vatican usage remains strict. It divides the "Princes of the Church" into four hierarchical groups. As cardinal-priests Turkson, O'Brien and O'Connor take precedence over mere cardinal-deacons, such as the sonorously aristocratic Italian, Andrea Cordero Lanza di Montezemolo.

The young Turkson did well at primary school. He had a talent for mastering scripts of plays and poems, and a love of maths which brought him the nickname Archimedes. But until his teen years, his Catholic father, Pius – a carpenter in the manganese mining town of Nsuta Wassa – and Agnes, his Methodist mother, saw him as far too boisterous for the church.

Speaking at his mother's funeral he recalled her begging him with tears in her eyes to stop being such a tearaway. Because of his mother's tears, he stuck to his books in the seminary, got his GCEs and became a priest in 1975. In addition to his native Fante and English, he learnt French, Italian, and German, as well as Hebrew, Aramaic, Arabic and Greek and devoted himself in his mid-twenties to scriptural studies.

He returned to Ghana to teach: a pupil recalled that he had inherited his father's practical streak and was keen on using tools and gardening. "We all wondered what flowers he would plant in the school garden but he ended up planting cabbages."

As a priest in his forties he was preparing for a doctorate at the Biblicum, the famous biblical institute in Rome, when the Archbishop of Cape Coast, John Kodwo Amissah, died. At 43 he was offered – and reluctantly accepted – the job in Ghana's former capital, dominated by its castle, a reminder of the horrors of the trans-Atlantic slave trade. Cape Coast Castle was the last halt in Africa for thousands – including, possibly, Michelle Obama's forebears – before they were sent to the American plantations.

Archbishop Turkson was named Cardinal 10 years later. In October last year he was called to Rome and made president of the Pontifical Council for Justice and Peace, charged with getting Catholic social teaching accepted worldwide. He has spoken out against the environmental impact of global businesses and he accuses them of doing too much open-cast mining in Ghana, just because it's easier and cheaper. Consequently, he said, villages are wiped out. "They build a few shacks for the displaced people and leave it at that.... When you move people off land they have been farming, you are also taking away their jobs and livelihoods. People think mining companies bring jobs, but when we visited those areas we found far more jobs were lost than new ones created. After the surface mining, the forest cover and the top soil are gone. What's left is a deep, gaping crater." Governments, he said, must not sign away their environmental future.

Cardinal Turkson is proud that the church is strong in Africa, and recently chaired a successful synod for African bishops at the Vatican, another sign of his growing stature. But he recalls how the record has been besmirched by war and genocide. "The Rwandans," he has said, "were supposed to be 80 per cent Catholic, but they forgot they were Catholic, and they forgot they were Christian."

He shares Pope Benedict's worries about the church in Europe. European missionaries first took the Catholic faith to Africa, and African Catholics see Europeans as their spiritual forebears. "It's indispensable that we see Christianity come back to Europe," he once told the Catholic News Service. "If Europe should become less Christian, it gives us a sense of being orphans, of having an experience of faith without parents."

While he has been mooted as a worthy successor to the 82-year-old Pope, as a fit 61-year-old his relative youth could count against him. John Paul II was elected when he was 58 and died at 84, and some electors may not want another reign lasting as long.

Cardinal Turkson has steered clear of the merciless infighting indulged in by some cardinals, which has caused Pope Benedict to remind them of the words of St Paul: "If you bite and devour one another, take heed that you are not consumed by one another."

He also has no obvious connection to the late Father Marcial Maciel, the incestuous Mexican head of the Legion of Christ, who was a child molester. Unlike Cardinal Franc Rodé from Slovenia and Cardinal Angelo Sodano, the most senior cardinal and former friend of Chilean dictator General Augusto Pinochet, Cardinal Turkson has no record of fawning over Maciel. Nor is he overshadowed by corruption allegations like the Archbishop of Naples, Cardinal Crescenzio Sepe, whose property deals are being investigated by Italian police.

The bookies are offering a generous 41-1 on the papacy going to Cardinal Turkson. It may take a while to come in, but it looks like a good outside bet.

Merchandise: No Pope on a rope... well, not yet anyway

Next month's four-day papal visit to Britain has already spawned a mountain of tasteless tat, bizarre parties and weird literature catering for both the devoted and the sceptical.

* Fans of Pope Benedict XVI can choose from a dizzying array of souvenirs, including a commemorative gold medallion – a snip at £775; 10 metres of papal bunting; or a life-size cardboard cut-out of the pontiff.

* Those who would rather the man in white refrained from setting foot in the UK have got their own merchandise. A T-shirt with a condom on the front and a church on the back carries the dual slogans: "Protects Lives" and "Protects Itself", while another carries the more blunt message "Pope? Nope!".

* Publishers are also looking to make money from the visit. Over the next month, new titles hitting the shelves include The Pope Is Not Gay by Angelo Quattrocchi, an irreverent look at homophobia in the Catholic church; The Case of the Pope: Vatican Accountability for Human Rights Abuses, by Geoffrey Robertson, and several rushed-out biographies, not to mention the distribution of a million copies of the liturgies and events of the papal visit, available from churches.

* Even celebrities are taking sides, with reality television stars Susan Boyle and Michelle McManus preparing to sing for the Pope in Glasgow on 17 September, while both AC Grayling and Peter Tatchell will be spearheading a protest in Hyde Park, central London, the following day.

Emily Dugan