With his family, he left Baghdad as an infant aged two and has lived outside Iraq ever since, attending a Lebanese high school and a British university. Tall and elegant, Sharif Ali enjoys fencing and speaks English in the clipped tones of the Home Counties. And yet he is planning to play a role in the emerging politics of his lost homeland as the leader of the London-based Constitutional Monarchy Movement, one of the groups that form the Iraqi National Congress (INC).

Sharif Ali has credentials. His mother Princess Badia, daughter of another deposed king, Ali of the Hejaz, was the aunt of King Faisal II, slaughtered during the 1958 revolution. But there is not a hint of doubt in Sharif Ali's determination to offer himself to a country that so violently rejected the monarchy and his family. 'The most important thing is for Iraq to decide whether it wants a monarchy or another system,' he said on 9 April.

In fact, Sharif Ali is not the only contender for the title of pretender to the throne of Iraq. Prince Raad bin Zeid, aged 67, a graduate of Christ College, Cambridge and Lord Chamberlain at the court of King Abdullah II of Jordan, is head of the Hashemite dynasty. His father was the youngest of the four sons who survived to adulthood of Sharif Hussein, leader of the Arab revolt of 1916-18, and the only one who was not made king after the collapse of the Ottoman Empire. Speaking in an interview with the Financial Times in early April, Prince Raad said he would not go back to Iraq 'until asked by the people'.

The third Hashemite with a potential claim is former Jordanian crown prince Hassan bin Talal, uncle of King Abdullah. The word from Amman is that Hassan is interested in a role in post-crisis Iraq, possibly as UN mediator.

Sharif Ali will soon have to deal with the realities of a country turned upside down in less than a month by the force of American and British arms. Having a fixed plan is probably unwise, as opposition figures returning to Iraq are saying surprising things.

'The government of Iraq should be put in the hands of the Iraqi people as soon as possible, or there will be a growth in fundamentalism,' Hamid al-Bayati, London spokesman for the Supreme Council for the Islamic Revolution in Iraq (Sciri), said on 11 April. Sciri is a Tehran-based umbrella group supported by Shia organisations and individuals.

Even Ahmed Chalabi, president of the INC, a group that has received more than $31 million from the US since 1999, is not sticking to a predictable script. The Americans flew him into Nasiriya on 8 April amid claims he and his organisation were Washington's puppets. Chalabi's response has been a series of statements in which he called for an early end to US military rule.

The response to returning exiles from ordinary Iraqis, some at least of whom benefited from a quarter-century of Baathist rule, is one of the larger uncertainties of the Iraqi adventure. The news was initially more bad than good. American troops were greeted with sullen resignation more often than with joy. In the days following the collapse of the regime, looting and lawlessness erupted from Basra to Baghdad. Nervous American troops, fearful of guerilla attacks by remnants of the regime, mistakenly shot dead at least five civilians in the capital alone on 10 April, and other fatal incidents involving coalition forces have been reported since. The same day, Abdulmajid al-Khoei, the politically moderate son of the late Shia leader Ayatollah Sayed Abdul-Qasim al-Khoei, was stabbed to death during a meeting at the mosque of Imam Ali in Najaf, one of the spiritual centres of the Iraqi Shia faith.

The horror in Najaf has highlighted the conflicts within Iraq's Shias, numbering up to 16 million people and accounting for 65 per cent of the total population. Reports from Najaf suggest that Al-Khoei was killed by a group who rejected his support for the coalition attack and involvement with US efforts to forge an alliance of opposition groups in the run-up to the war. He had been a member of working groups in the Future of Iraq project organised by the US State Department in 2002. Similar motivations are attributed to a group who on 13 April surrounded the home of Grand Ayatollah Ali Sistani and ordered him to leave Iraq. Sistani, born in Iran, had called on Iraqi Shias not to resist the coalition, dismaying Sciri and anti-regime elements in his community.

The only consistently predictable response has been in the north. The streets of Irbil, Suleimaniya and Salahuddin, towns controlled by the Kurdistan Regional Government (KRG), were filled with celebrating people on 8 April as Baghdad fell to coalition troops. Conforming to their impetuous reputation, Kurdish militias precipitously seized Kirkuk on 10 April. As forecast, the Turkish government threatened to invade if the Kurds failed immediately to withdraw and hand the city, which is the principal oil town of the north, over to the US. Mosul fell in a similar unplanned manner to Kurdish fighters working with US special forces the following day. Over the next 48 hours, at least 20 people were killed in fighting in the city between Kurds and Arabs, according to reporters.

In the confusion and fear, however, a clear message is beginning to emerge. The US, the uninvited liberator of Iraq, is far from welcome. Delighted as many are by the destruction of the regime of Saddam Hussein, the view of US motives is sceptical across the political spectrum. 'Everyone I know from Iraq living here says, whether it is true or not, that the US is after Iraqi oil,' says a UK-based engineer who lived in Iraq in the 1980s and has maintained links with the Iraqi community ever since.

The first organised test of national opinion within Iraq after the fall of the Baathist regime came on 15 April, at an opposition meeting organised by the US near Nasiriya. The gathering was a stuttering start to the process of political reconstruction. Sciri boycotted it and there was a disproportionate representation of Iraqi-Americans and others, like Chalabi, who have accepted at least part of the American agenda for Iraq and the Middle East.

The next phase in the war for Iraq will be to establish the legitimacy of the future government of a country that has never had an election based on a universal adult franchise. It is a struggle that is likely to be both long and difficult. n