Australia's governor-general, Sir Peter Cosgrove, likened the trip to a similar tour Down Under taken in 1927 by William's great-grandfather, the Duke of York – later King George VI – and his wife.
"Accounts of their visit note the deafening cheers of the crowds, the fervent and spontaneous greetings of those they met, and the Duchess won hearts from the start – all words that could describe the last couple of weeks," Cosgrove told the 100 guests in the drawing room of the residence in Canberra.
William and Kate, of course, brought Prince George on this trip. Likewise, in 1927, George and his wife (later known as the Queen Mother) were young parents to a 13-month-old Elizabeth, who 25 years later would become queen.
Kate, 32, in a white dress by American designer Lela Rose, and William, 31, left George with his nanny Maria Borrallo and were joined at the party by guests including Victoria Cross recipient Corporal Ben Roberts-Smith (Australia's most decorated modern soldier) and former INXS guitarist Kirk Pengilly and his professional surfer wife Layne Beachley.
Earlier, at a reception for 600 guests at Parliament House, the couple met with film stars, Olympic athletes, fashion designers, politicians and more.
William told one guest that the Blue Mountains and Manly Beach were among his favorite spots in Australia, and joked about his bathing suit. "He said he was hoping to rip off his pants with velcro down at the beach with [Prime Minister] Tony Abbott to reveal their Speedos," Vicki Kelly, wife of parliament member Craig Kelly, told reporters.
Kate, meanwhile, rued her missed opportunities for shopping.
"She's so beautiful. I asked her about Australian fashion and she said she was really interested in the designers here," said Network 10 anchor Angela Bishop. "Kate said she really wanted to go out shopping and had been driving through cities looking out the window peering into show windows. I think she was a little disappointed that she couldn't shop here."
Rob Griffith / AP