Before William and Kate, before Charles and Di, before Liz and Dick (I and II), before any of the "storybook" weddings of the past several decades, there was the fairytale wedding of the last century: the April 1956 nuptials of Grace Kelly and Prince Rainier III of Monaco. The tale of the American movie star and Philadelphia native marrying the prince of a small, sensationally wealthy city-state was simply too perfect to ignore — and for months leading up to the event, from the time of the couple's engagement until the two ceremonies (civil and religious) that formalized their union, the Hollywood princess and the real-life prince were hardly ever out of the news.
Here, LIFE.com presents photos — many of which never ran in LIFE magazine — from the moment the couple announced their engagement in January 1956 until they were married three and a half months later in Monaco. In an issue published a few weeks after the wedding, LIFE framed the singular phenomenon for the magazine's millions of readers:
Largely ignored throughout its long history, the pint-sized principality of Monaco last week enjoyed a beautiful modern recognition. Grace Kelly, daughter of a millionaire former hod carrier [in short, a construction laborer] from Philadelphia and the virtual princess of moviedom's make-believe world, was getting married there. She was becoming a princess officially by her marriage to Monaco's Prince Rainier, who holds 139 other titles and is absolute ruler of a 370-acre realm with 20,000 subjects.
Throughout the palpitant anxieties which are the lot of every bride, Miss Kelly was everything the enthusiastic Monegasques could have wished. She had to go through two weddings, separately required by the Napoleonic Code of Monaco and the laws of the Roman Catholic Church. . . . [After the first she assumed the title] Her Serene Highness, Princess Gracia Patricia of Monaco. [During the second] she became a wife indeed when she helped the nervous Prince Rainier settle the ring on her finger.
And so an old-style fairy tale came to its appropriately romantic conclusion, but only after a number of modern day variations and additions had come to pass.
The princess-to-be had barley set foot in Monaco when the principality and much of the rest of Europe were there bearing gifts. The wedding presents ranged from the fabulous to the foolish. Among the more practical was a Rolls-Royce, among the less useful a gold and bone hatchet.
All the loose wealth gathered there acted magnetically on Europe's thieves. $50,000 worth of jewels swiped from the wife of a pal of Grace's father . . . $8,000 in gems lifted from the hotel room of one of the bridesmaids.
After their wedding, Monaco's newlyweds wasted no time starting a family: Nine months and four days later, Grace gave birth to Princess Caroline, their first of three children. The couple was married for 26 years, until the princess' death in 1982 from injuries sustained in a car accident. The prince, who never remarried and who died in 2005, is buried beside his wife in the Grimaldi family vault, inside the Monaco cathedral where they wed.
Liz Ronk, who edited this gallery, is the Photo Editor for LIFE.com. Follow her on Twitter at @LizabethRonk.