#RoyalBaby tweets even surpassed those about Pope Francis, the website Wired.it said. Out of the 18,000 or so tweets, 11,800 were made by different people.
Tweeters injected a little humour into their messages of goodwill, with one making a reference to William's younger brother, Prince Harry, being snapped naked last year: "A son has been born to Kate and William in England. It seems that at the time of birth, the child was naked, just like uncle Harry."
Another quipped: "Considering the long labour, the only explanation is that Kate is about to give birth to a secretary of the PD" [Italy's right-wing People of Freedom party].
Meanwhile, Italians were also reported to be among among the top commentators about the birth on Facebook. They were eclipsed only by Britons, Americans and Canadians.