Crowned to a chorus of approval: Tom Stacey joins the revellers at the coronation of the king of the Baganda, Uganda's most powerful tribe

KAMPALA - Something remarkable happened here in the heart of Africa at the weekend. Ronald Mutebi was crowned as kabaka of Buganda. You may see the coronation of King Ronnie as no more than a sop to traditionalists, a cynical public relations ploy by the leader of a black republic with no secure political roots of his own, a reprise of pageantry that sidetracks the will-to-power into ethnic theatre. But you would be mistaken. What we witnessed on the crest of Buddo Hill, dominating the downs around Kampala, is one of those moments that mark the surfacing of a fresh truth. I speak of the re-emergence of the tribe as the only political entity that in the long run is going to work effectively in post-colonial Africa.

Have I perhaps been touched by those heathen rituals, which began before dawn on Saturday and continued unabated for almost three days? Certainly I have. But rituals such as these represent the realities of black African allegiance - in this instance among King Ronnie's Baganda, whose tribal territory contains the capital, the airport, the most water and productive land, and about 4 million of Uganda's 18 million citizens.

In the pre-dawn darkness of Saturday, the entire leafy acreage of Buddo was already aswarm with tribespeople gathered for the day's events. Arriving on foot, by boat, in charabancs, they camped all night. Some of us, emerging from sleep, were burst upon by mock warriors rushing to make a slaughter of us mock- enemies of Buganda; and soldiers present, keeping order, confusing fantasy for fact, cocked their AK47s. But we accepted ritual defeat and death at once for a sovereign Buganda.

Then, all at once, Ronnie was in our midst. He had arrived at Buddo's summit in the dark in his black Mercedes with outriders in ghostly white, with scarlet flashes and berets, on their Hondas and Yamahas, and his usual cortege of Mitsubishi Pajeros, and a genuinely antique British Land Rover. Out he leapt, and holding aloft a reed switch, passed commandingly beneath a symbolic lich gate of thatched reeds to enter this tribal haram, and this semi-sacred area of the Baganda heartland.

Word of his presence spread rapidly. His subjects' ululations rolled across the ridge-top on a wave of joy. At the first compound of 20ft canes, members of the Lungfish clan of his late father, King Freddie, Kabaka Mutesa II, performed a refrain lamenting his death, while Ronnie himself was ritually washed of his tears of mourning.

King Freddie's death took place in Bermondsey, south London, in 1969. The then prime minister of Uganda, Milton Obote, with Idi Amin as his military commander, had flown him out in 1966 after an armed assault on his palace, and formally abolished all the country's four monarchies the next year.

Earlier last week, in conveying Idi Amin's contrite good wishes (entrusted to me by telephone) to young Ronnie on the restoration of the kabaka-ship, I mentioned Amin's conviction that his father had died not, as the coroner had found, of alcohol but from poison skilfully administered for the purpose of snuffing out for ever the Baganda's hereditary 'Queen Ant'.

Now they have a 'queen ant' again. With the sun risen, Ronnie progressed through the vast throng to the grove where the true coronation would be enacted. There, upon an anthill carpeted with leopard hides, clan elders draped him in four blankets of barkcloth, a cowhide cloak and leopard skin. A tarboosh, adorned with shells, was placed on his head. A clan elder, who also appeared to be a Catholic bishop, gave him ritual water from a gourd; another handed him a sword; a third, two spears. Ronnie thus swore to defend his kingdom to the death. Then he sounded the sacred drums by which the kabaka's authority descended upon him.

Throughout all this he was being watched, from beneath an awning decorated with the national, rather than the Buganda colours, by a silent figure in a high-backed chair: Lieutenant- General Yoweri Museveni, president of the republic, by whose personal sanction this coronation was occurring.

With all the dressing-up done, young Ronnie was foisted on the leopard-draped shoulders of his official bearer and carried through the delirious masses of his people. And I, four paces behind, helped his court stragglers to keep the overexcited at a respectful distance.

Such joyousness] Such ululation - from thousands upon thousands of throats: the old, the young; the high, the low; the educated, the unlettered; Christian and Muslim. My ears ring with this amazing chorus as I write this dispatch. But the head remains clear. As clear, I suggest, as that of the other observer, the principal guest, whose power is Caesar's here: President Museveni, in his dark, cautious suit and red tie.

Here is one who started out steeled in a ruthless Leninism, who acquired supreme power by the gun, a committed republican, mastering his patch of archetypal Africa by the usual mix of repressive acts and promises of betterment. What genie had he just unbottled? Mr Museveni has set his conditions, naturally, for the restoration of this and the other, smaller monarchies of southern Uganda. They are to be chastely 'cultural', in no way 'political'.

Yet he, too, will know that genies have their own will. Handsome young Ronnie, with his frown of cold command, has found his role. He is instantly a force in this republic. How long before this chamber of tribal representatives, when they are resummoned, loses the misty line between 'culture', which is all the tribe is supposed to mean, and power as the only sustainable allegiance in black Africa?

Mr Museveni knows the gamble of this kind of realism. Tribal authority so boldly rekindled might lend him a depth of glow and a popular warmth he badly needs. Or its patriotism could burn him up.

The writer has been reporting on African affairs since 1954.