Before a flawless exchange of vows, a veiled Middleton wearing a laced dress with a long train, the first "commoner" to marry a prince in close proximity to the throne in more than 350 years, walked slowly through the 1,900-strong congregation.
As they met at the altar William, second in line to the throne, whispered to her, prompting a smile. The Archbishop of Canterbury Rowan Williams declared the couple married with the words: "I pronounce that they be man and wife together."
Tens of thousands of people thronging the streets outside cheered when they heard the words, and again as the newly-weds left the abbey in a 1902 open-topped state landau carriage bound for Buckingham Palace, the queen's London residence.
Huge cheering crowds strained to catch a glimpse of the beaming couple as well as the military bands in black bearskin hats and cavalrymen in shining breastplates who escorted them to the palace.
Kate waving to the crowd the day before the ceremony.
Prince William makes Kate Middleton his princess by putting the wedding ring on his bride’s finger at Westminster Abbey, London, yesterday.
Middleton's dress, the subject of fevered speculation for months in the fashion press, was a traditional ivory silk and satin outfit with a lace applique and train.
It was designed by Sarah Burton of the Alexander McQueen label, named after the British designer who committed suicide.
The bride wore a tiara loaned by the queen and the diamond and sapphire engagement ring that belonged to William's mother Princess Diana, who was divorced from Prince Charles in 1996, a year before her death in a car crash in Paris aged just 36.
Middleton, the 29-year-old whose mother's family had coal mining roots, is a breath of fresh air for the monarchy, which has in the past been accused of being disconnected from ordinary Britons. She is seen as having the common touch.
The royals' cool reaction to Diana's 1997 death contrasted with an outpouring of public grief and marked a low point for the family. Some questioned whether the institution, a vestige of imperial glory, had outlived its unifying role in a modern state divided by partisan politics and regional separatism.
Thousands of people from around the globe were outside the abbey, many of them camping overnight for the best view of the future king and queen and fuelling the feel-good factor that has briefly lifted Britain from its economic gloom.
"People watching this at home must think we're completely mad, but there's just no comparison," said 58-year-old Denise Mill from southern England. "I just had to be here."
The crowd entered into the festive spirit on a day when threatened rain failed to materialise by wearing national flags and even fake wedding dresses and tiaras.
Hundreds of police officers, some armed, dotted the royal routes in a major security operation. Plainclothes officers mixed with the crowds who were packed behind rails.
The marriage between William and Middleton, dubbed "Waity Katie" for their long courtship, has cemented a recovery in the monarchy's popularity.
A series of scandals involving senior royals, Britain's economic problems and Diana's death after her divorce from Prince Charles led many to question the future of the monarchy.
But Middleton's background, William's appeal, the ongoing adoration for his mother and a more media-savvy royal press team have helped to restore their standing with the wider public.
A Daily Mail survey showed 51 per cent of people believed the wedding would strengthen the monarchy in Britain, compared with 65 per cent who said the marriage between Prince Charles and Camilla Parker Bowles in 2005 would weaken it.
Bells pealed loudly and trumpets blared as 1,900 guests earlier poured into the historic abbey, coronation site for the monarchy since William the Conqueror was crowned in 1066.
Queen Elizabeth, other royals, Prime Minister David Cameron, David and Victoria Beckham, the footballer-pop star couple, and singer Elton John were among famous guests at the abbey.
They joined 50 heads of state as well as charity workers and war veterans who know the prince from his military training.
Middleton has been given the title Her Royal Highness, The Duchess of Cambridge after the queen made her grandson William the Duke of Cambridge to mark the marriage
