When Britain's Prince Harry and Meghan Markle walk down the aisle on Saturday the moment will be beamed live by satellite around the world.
It is a televisual tradition that began 62 years earlier with the marriage of prince Rainier III of Monaco and Grace Kelly, an iconic actress at the height of her Hollywood glory.
Filmed in black and white, the images of the 1956 ceremony in the European principality were the first of a royal wedding to be transmitted live. Back home in America Kelly's fans had to wait to view the starlet's fairytale wedding, but its impact on the popular imagination was no less great.
The images were grainy and uncoloured and TV ownership was not the norm. But the ingredients for a showbusiness sensation were perfect: an American, like Meghan Markle, with the charisma to lift Monaco out of its post-war malaise and a young 32-year-old prince looking for that touch of glamour to revive his micronation.
Realising the benefits of televising the event, and strengthening its political and economic ties to the United States, Monaco made every effort to make the ceremony a media event of planetary importance.
On 19 April 1956 the transmission went out on the new Eurovision network -- just three years after the coronation of Queen Elizabeth was transmitted live in 1953. Thirty million Europeans spread across nine different countries tuned in to witness the wedding. Meanwhile 1,800 journalists had invaded "The Rock" of Monaco, a record for the time.
"It was shown on American television, but not live because films had to be sent by plane. In those days there weren't any satellites and the film rolls had to be canned at the end of the ceremony before being sent to the United States," documentary maker Frederic Laurents said.
"In the days that followed it was also shown on newsreels in cinemas."
"We had to wait another 25 years, for the marriage of prince Charles and Diana, for another television phenomenon on the same scale," he added.
"Rainier was very conscious of the power of the media. His wedding was designed as an event to put Monaco back in the spotlight at a time when it was vegetating and none of the post-war papers had any interest in it."
- Silk, tulle and mink -
Rainier's love affair with a Hollywood princess was a shot to the arm for the press, which became fascinated with the American raised in a rich Irish catholic family in Philidelphia.
It was a photographer for Paris-Match who had the idea to introduce the prince to the actress, the muse of Alfred Hitchcock, during the 1955 Cannes film festival. At the height of her career, Grace Kelly had just won an Oscar for best actress. Alongside Ava Gardner and Marylin Monroe, she was one of the three main stars of the moment.
The suspense over her wedding dress, provided by Holywood studio MGM, was painstakingly managed. It was only two days before the ceremony that the public found out it was to be a long-sleeve ivory dress, designed to flatter the figure of the actress when seen from behind as she stood before the altar.
In his despatch from the cathedral one of AFP's special correspondents told of the pomp of the ceremony: the children's choir, the organ, 1,100 numbered seats with each member of the audience clothed in silk, tulle and mink.
When Monsignor Gilles Barthe asked the sacred question, first to Rainier then to princess Grace, the silence was shattered by the shutters of hundreds of cameras. In the media frenzy only he could hear them both say "yes".
Prince Rainier III of Monaco married US actress Grace Kelly on April 19, 1956
It was only two days before the ceremony that the public found out Grace Kelly's dress was to be a long-sleeved and ivory coloured
Images of Prince Rainier III of Monaco and Grace Kelly's wedding were beamed across nine countries in Europe