The Church of England could see its first black Archbishop of Canterbury following the departure of Rowan Williams from the post.
John Sentamu, 62, the Archbishop of York, is widely viewed as front-runner to replace Rowan Williams when he leaves at the end of this year.
Williams is to step down from his position to become Master of Magdalene College, Cambridge. In a statement Lambeth Palace said: "Archbishop Rowan Williams has today announced his acceptance of the position of Master of Magdalene College, Cambridge with effect from January 2013.
Dr Sentamu, the sixth of 13 brothers and sisters, and a former barrister and judge, came to the UK in 1974 having fled Uganda where he was a critic of the dictator Idi Amin.
Dubbed by some as "cleric of the people", he is known for his high-profile interventions.
In 2007 he cut up his dog collar on live television in a dramatic protest against Robert Mugabe's rule, vowing never to wear the symbol of his office again until the Zimbabwe president had been removed from power.
Dr Sentamu also once pitched a tent and camped in York Minster for a week, foregoing food, in solidarity with those who had suffered in the Middle East conflict.
The Archbishop has gained a reputation for supporting the armed forces - sky-diving to raise money for families of servicemen wounded or killed in Afghanistan - and for speaking out against bankers and traders responsible for the financial crisis.
He has called for the English to mark St George's Day properly on April 23, warning that the failure of England to rediscover its culture would lead only to greater political extremism.
Dr Sentamu's enthronement in 2005 featured a ceremony with African singing and dancing and contemporary music, with Dr Sentamu playing African drums during the service.
Such is his popularity in his archdiocese of York that he was named Yorkshire Man of the Year in 2007.
As Bishop of Stepney in east London, Dr Sentamu acted as an adviser to the inquiry into the racist murder of Stephen Lawrence. He has also campaigned against guns, knives, drugs and gangs.
More recently, he attracted controversy - and racist emails - when he spoke out against gay marriage. Dr Sentamu is married with two grown-up children and two grown-up foster children.
Other possible contenders to replace Dr Williams include Richard Chartres, the Bishop of London.
Dr Chartres, 64, who is close to members of the Royal Family, gave the address at the marriage of the Duke and Duchess of Cambridge last year and is known for campaigning on environmental issues.
Liverpool-born the Rt Rev Nick Baines, 54, Bishop of Bradford, is also viewed as a contender for the post.
Highly educated and articulate, he is known as the "blogging" bishop, in recognition of his enthusiastic approach to using new media.
The Rt Rev Tim Stevens, 65, Bishop of Leicester, who leads the Church of England bishops in the House of Lords, and has recently clashed with the Government over the proposed benefits cap, could also be a possible contender.
Who will replace Rowan Williams?