Clinging to his handler's trouser leg, Knut emerged from his enclosure into the chill spring day, finally silencing a group of small children who had been crying "Knut is cute, we want Knut!" for over an hour.
Other children hanging off a nearby wooden climbing frame waved at the baby polar bear, shouted "knooot!" and photographed him on their mobile phones as he ambled over the rocks and dipped his paws into the moat separating him from an audience including around 400 journalists from as far afield as South America, Pakistan and Uzbekistan.
They had waited since early morning with patience usually reserved for a member of the royal family or a pop star, poised on viewing ladders with long-lens cameras to capture Knut's first public appearance.
The celebrity status of the animal, now three and a half months old, has increased daily since his birth. The strength of the Knut brand was visible yesterday in the stuffed bears being sold next to his enclosure, the polar bear ties sported by his keepers, and the children's polar bear rucksacks.
Knut has his own podcast and a webcam in his enclosure, and New York photographer Annie Leibovitz has already dropped in to snap him for an environmental campaign.
Knut's story has tugged at German heart strings. Rejected by his mother, Tosca, a retired east German circus bear, he was the first polar bear to have been born and survived in Berlin for more than 30 years. His brother succumbed to an infection, but the guinea pig-sized Knut, who faced almost certain mauling by his mother, was put in an incubator and bottle-fed every two hours. He survived to become part of a media circus that Berlin zoo has not experienced in its 163 years.
"The thing that's caught people's imagination is that he nearly died," said keeper Ragnar Kühne.
"His mother rejected him and according to the laws of nature he should have died," said Bruno Gassmann, selling stuffed bears. "But it's thanks to the hard work of the keepers and his own strong will he's survived and that's why we're celebrating."
But Knut's entry on to the international stage came only this week, as a result of the outcry prompted by animal rights activists suggesting in the tabloid Bild that it would have been better to have killed him at birth.
He would, they argued, struggle to live with his own kind having spent his first months with his carer, Thomas Dörflein, who strums Elvis Presley's Devil in Disguise on his guitar at Knut's bedtime and has been left covered in cuts and bruises from his constant rough and tumble with the cub.
Schoolgirls campaigned with placards outside the zoo's gates, outraged that Knut might face a lethal injection. There was a collective sigh of relief when the zoo said it had no intention of putting down its most prized exhibit.
He is tipped to be the cover boy of next week's German version of Vanity Fair.
The environment minister, Sigmar Gabriel, yesterday seized the opportunity of a rare feelgood moment, joining Knut in his enclosure for his public debut. He cautiously patted the sharp-clawed bear's coat for the world's press and announced he would adopt Knut as a mascot for an international environment conference in Berlin next year.
"There's no other animal that better symbolises global warming," said Mr Gabriel. "Over the last few years the polar bear population has decreased by 10% and the mammals have been losing weight as their sources of food have decreased. In short it is one of the most endangered species on the planet."
Adrianna Zielinska, 12, visiting with her class from St Franziskus school in south Berlin, said: "I did think when he was rejected by his mother that he should have been left to die for his own sake, but he's clearly a real fighter, so I'm glad he was given a chance."
Thousands of column inches have already been devoted to details of every aspect of Knut's life, from his diet and favourite games to his penchant for sleeping in a hammock.
Published yesterday, a blurred picture taken by a visitor to the zoo of Knut's parents copulating even claims to capture the very moment when the star polar bear was conceived.
