Here is a look at other royal weddings and some of the scrutiny that surrounded them.
William and Catherine
Prince William and Catherine, the former Kate Middleton, were married in April 2011. Viewing estimates for the ceremony hovered in the three billion range, with more than a million lining the route of the royal procession. Wedding fever carried across the ocean, with many American businesses and restaurants holding events to commemorate the nuptials.
The couple met when they were students at St. Andrew’s in Scotland, and Kate’s wedding to Prince William was unusual in the context of the royal family, because she was a commoner. Their marriage was seen as an example of how members of a new generation of royals were taking spouses of choice rather than of royal lineage after the marriage of Prince Charles and Princess Diana ended in divorce.
William and Catherine are expecting the birth of their third child in April.
Charles and Camilla Parker Bowles
Charles, the Prince of Wales, and Camilla Parker Bowles were married in April 2005. It was the second marriage for both, and each had two children from the first marriage, all of whom attended the civil service and church blessing in Windsor.
The marriage made Camilla, his longtime mistress, the Duchess of Cornwall and wife to the heir of the throne. The wedding was a sign of how things had changed from the era when royals were not allowed to marry divorced people.
Charles and Diana Spencer
There were 2,500 guests inside St. Paul’s Cathedral, with television viewers around the world witnessing what The Times described as a “fairy tale come to life” when the 32-year-old prince, in naval uniform, married the 20-year-old daughter of an earl.
The marriage vaulted Lady Diana into the role of a national emissary for Britain as the Princess of Wales as she threw herself into charitable work worldwide. The couple had two sons, Prince William and Prince Harry.
Prince Charles and Princess Diana separated in 1992 and divorced in 1996. Their union was overshadowed by Mrs. Parker Bowles’s relationship with Prince Charles, described by Princess Diana to a BBC interviewer in 1996 as “three of us in this marriage, so it was a bit crowded.”
Princess Diana died in a car crash in Paris in 1997, setting off a flurry of news coverage worldwide.
Margaret and Antony Armstrong-Jones
Princess Margaret, the sister of Queen Elizabeth II, married Antony Armstrong-Jones in July 1960. Mr. Armstrong-Jones, a photographer, became the Earl of Snowdon. He took Princess Margaret’s official portrait in 1958, and they connected again at a dinner party and began a secret affair.
The union was seen by many as a breakthrough in class barriers — Mr. Armstrong-Jones was the first British commoner in four centuries to marry a king’s daughter.
Edward VIII and Wallis Warfield Simpson
King Edward VIII abdicated in December 1936 so he could marry his twice-divorced American mistress, Wallis Warfield Simpson.
The Church of England opposed the marriage at the time, but the king chose love over his royal duties, allowing his younger brother to take his place as King George VI. Edward and Ms. Simpson were married in 1937.