Kate and William become Duke and Duchess of Cambridge
Prince William has been made Duke of Cambridge, and his wife the Duchess of Cambridge, Buckingham Palace has said.
The prince has also taken the titles Earl of Strathearn and Baron Carrickfergus, linking him to Scotland and Northern Ireland.
He has been given the titles by the Queen to mark his marriage. Catherine also becomes her royal highness.
Giving new titles to a member of the Royal Family on their wedding day is a long-standing tradition.
When Prince Andrew married, he became the Duke of York, Earl of Inverness and Baron Killyleagh.
Prince Edward became the Earl of Wessex and Viscount Severn on his wedding day in 1999.
While the Prince of Wales did not take any additional titles when he married Lady Diana Spencer in 1981, he was already Prince of Wales, the Duke of Cornwall, Duke of Rothesay, Earl of Carrick, Baron of Renfrew, Lord of the Isles and Prince and Great Steward of Scotland and Earl of Chester.
The Dukedom of Cambridge was created in 1801 but became extinct on the death of the 2nd Duke of Cambridge in 1904.
Genealogist Charles Kidd, editor of Debrett's Peerage And Baronetage, said it was a good choice for the prince.
"Cambridge was generally spoken of as a high possibility. It has a long royal tradition, and is immediately recognisable as an English title, it's one of those places everyone has heard of."
Professor David Carpenter, of King's College, London, said there may have been consideration of using the title of Duke of Clarence but it had some unfortunate associations.
"Queen Victoria's grandson Albert Victor, who was second in line to the throne, was made Duke of Clarence when he reached full age, but he was a womanising philanderer who died in the 1890s."
'Doomed to failure'
The last holder of the title, Prince George, known as the 2nd Duke of Cambridge, was born in 1819 and was a grandson of George III and the only son of Prince Adolphus Frederick, the 1st Duke of Cambridge.
He served in the Crimean War and was promoted to commander-in-chief in 1887.
Indeed, once married, the newly-weds' carriage procession will pass a statue of the last duke sitting on a horse close to the Ministry of Defence in Whitehall.
The 2nd Duke of Cambridge refused to have an arranged marriage and declared such unions were "doomed to failure".
He had an unrecognised marriage to actress Sarah Louisa Fairbrother in 1847, who at the time was already the mother of two of his children and pregnant with his third.
But the Duke did not seek the sovereign's approval, the marriage was never recognised and Miss Fairbrother was never given the title the Duchess of Cambridge.
Instead she became known by the nickname Mrs FitzGeorge.
Strathearn has not been used as a title since the death of Alastair Windsor, the 2nd Duke of Connaught and Strathearn, who died in 1943.
By becoming Baron and Baroness Carrickfergus, the royal couple will be linked to County Antrim's oldest town.
An Irish Viscountcy of Chichester of Carrickfergus now held by the Marquess of Donegall was created in 1625 but Carrickfergus alone only existed as a title between 1841 and 1883.