Halfway around the world, royalist group Monarchy New Zealand said it had organized a national light show, with 40 buildings across the islands lit up in blue to commemorate the royal birth, including Sky Tower in Auckland, the airport in Christchurch, and Larnach Castle in the South Island city of Dunedin.
A similar lighting ceremony took place in Canada; Peace Tower and Parliament buildings in the capital, Ottawa, were bathed in blue light, as was CN Tower in Toronto.
The baby is just a day old — and may not be named for days or even weeks — but he already has a building dedicated to him.
Australian Prime Minister Kevin Rudd said an enclosure at Sydney's Taronga Park Zoo would be named after the prince as part of a gift from Australia. The government would donate 10,000 Australian dollars ($9,300) on the young prince's behalf toward a research project at the zoo to save the endangered bilby, a rabbit-like marsupial whose numbers are dwindling in the wild.
British media joined in the celebration, with many newspapers printing souvenir editions.
"It's a Boy!" was splashed across many front pages, while Britain's top-selling The Sun newspaper temporarily changed its name to "The Son" in honor of the tiny monarch-in-waiting.
The birth is the latest driver of a surge in popularity for Britain's monarchy, whose members have evolved, over several decades of social and technological change, from distant figures to characters in a well-loved national soap opera.
"I think this baby is hugely significant for the future of the monarchy," said Kate's biographer, Claudia Joseph.
For some, though, it was all a bit much.
"It's a baby, nothing else," said Tom Ashton, a 42-year-old exterminator on his way to work. "It's not going to mean anything to my life."
Associated Press writers Gregory Katz, Paisley Dodds, Maria Cheng and James Brooks in London, Rod McGuirk in Canberra, Australia, and Kristen Gelineau in Sydney, Australia, contributed to this report.
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