Having first met in 2000, Albert and Charlene made it official when they were married in a civil ceremony 11 years later.
The couple tied the knot in the Throne Room of the royal palace, with Charlene looking nothing short of princess-perfect.
In a beautifully cut sky-blue suit that oozed understated glamour, Charlene was radiant as she made her first appearance as a royal on the palace balcony. It had been 55 years since a new sovereign princess had greeted the people of Monaco from that exact spot.
Fashion commentators were quick to dub the colour "Charlene blue" and the princess later explained: "It's a collaboration between me and Karl Lagerfeld. We wanted something to match the colour of my eyes. It's my creation and I'm proud of it."
If the civil service was an intimate union of husband and wife in front of their nearest and dearest, then Saturday's religious ceremony was a chance for Monaco to invite a global audience to salute their new sovereign princess.
On 2 July 2011, Charlene stepped out in a silk Giorgio Armani bridal gown. It was simple, yet dazzling; regal yet unassuming. True to form, down-to-earth Charlene had gone for understated sophistication.
The dress, which required months of handiwork, was cut from 130 metres of silk, studded with 40,000 crystals and embellished with 20,000 teardrops fashioned from mother-of-pearl.
It gave centre stage to the bride's natural beauty and elegance, showing off her slender yet statuesque silhouette to perfection.
Charlene, the newest member of the Grimaldi family looked simply stunning, arriving at the palace on the arm of her father Michael Wittstock.
The atmosphere in the Cour d'Honneur, the palace's main courtyard, was nothing short of electric as Albert and Charlene married in a religious ceremony.
The courtyard had been turned into an open-air cathedral, where Monseigneur Bernard Barsi, Archbishop of Monaco, conducted a Catholic wedding mass consecrating the couple's marriage.
Watching the bride's every step intently as she walked down the aisle were the 3,500-strong congregation; plus 800 more celebrities and dignitaries who had been ushered into the inner courtyard including Karl Lagerfeld, Naomi Campbell and European royals such as Princess Victoria and Prince Daniel of Sweden, and Prince Mary and Prince Frederik of Denmark.
And millions more – watching on TV screens and through the internet across the globe – witnessed Charlene and Albert say "I do" for a second time.
The couple had wanted the largest number of guests possible to share in their big day, hence the choice of venue, rather than the cathedral, which holds only 500. Its cross, altar, and two chairs and kneelers for the bride and groom had been moved outside.
The mass was celebrated in French and Afrikaans and the South African flag flew high above the palace, reflecting the couple's partnership.
After the blessing of the rings, Albert placed a Cartier ring in 18-carat white gold and platinum on Charlene's finger.
Then it was the princess' turn. "Take this ring, it is a sign of your love and fidelity to Albert," said the Archbishop.
Trying to persuade the slightly reluctant ring onto his finger, the bride broke into a grin and laughed.
Laughter was followed by a peck on the lips – Charlene pulled back her veil and kissed the man who had courted her for 11 years.
Following the mass, the newlyweds walked down the aisle joined by six flower girls in traditional dress – children of Monagasque residents.
Albert and Charlene left under a hail of white petals and with bells pealing out, they were borne along the picturesque streets of Monte Carlo in a dark convertible Lexus.
The couple headed to the Sainte-Dévote Chapel for the traditional laying of the bride's bouquet.
Charlene, who had just officially stepped into Monaco's royal circle, gave a wave to wellwishers.
Charlene's face broke into a radiant smile for a moment as she re-emerged with her husband, her arm linked through his.
For most of the service she had cast her eyes downwards, as if trying to compose herself.
It seemed the scale and seriousness of the event had overwhelmed her – and the new princess only allowed herself to show her emotion later in the Sainte-Dévote Chapel, when her eyes misted over and she dabbed at them with a handkerchief.
Charlene stepped into her second dress of the day for the magnificent reception on Saturday evening. The pretty South African once again turned to her favourite Italian designer, changing into an Armani Prive cocktail dress.
The slimline gown featured a sheer top and a four-tiered skirt, which Charlene paired with peep toe shoes and an ivory clutch.
Albert and Charlene topped off a splendid religious ceremony with an even more lavish reception.
The centrepiece of the banquet was a towering wedding cake, made of 50 kilos of strawberries and 2,000 edible blossoms including Proteas, South Africa's national flower in honour of Charlene.
In keeping with their wish to respect the environment, many of the ingredients had been freshly picked from Roc Agel, the estate that Rainier III gave to Princess Grace as a wedding present in 1956.
After this lavish fare, the night sky lit up with a spectacular fireworks display, featuring a giant bouquet of 'fire flowers'.