Cannes crowned Love by Austria's Michael Haneke, the wrenching tale of a man and his dying wife, with its Palme d'Or prize as Europe swept the awards at world cinema's top showcase.
Haneke's octogenarian actors, French screen icon Jean-Louis Trintignant, 81, and Emmanuelle Riva, 85, bowled Cannes over in the story of Georges and Anne, an adoring couple whose bond is tested after she suffers a stroke.
His second Palme in three years, the win confirmed Haneke's status as arguably the most important film director working in Europe.
Haneke, 70, took the Palme d'Or three years ago for a very different work, The White Ribbon, a black-and-white study of malice in a German village on the eve of World War I, which some saw as a parable on the roots of Nazi savagery.
Hailed as a "masterpiece" by critics, the French-language Love marked a journey into tender new territory for a director better known for exposing the icy secrets of the soul.
Haneke's sober camera chronicles the intimate details of Anne's physical and mental decline, as Georges fulfils a pledge to care for her at home until the end.
'Promise to each other'
Both actors climbed on stage at the star-studded gala in the Riviera city to accept the award with Haneke, who dedicated it to his wife of 30 years.
"This film is an illustration of the promise we made to each other, if either one of us finds ourselves in the situation that is described in the film," Haneke told the audience.
Speaking for the rest of the jury, the designer Jean Paul Gaultier said Riva and Trintignant had delivered "the greatest emotion of all the movies we saw".
Choosing among 22 films from around the world, the jury headed by Italian director Nanni Moretti handed all but one prize to Europeans.
Cannes' best actor award went to Danish heart-throb Mads Mikkelsen, 46, searing as a man falsely accused of molesting a child in the psychological thriller The Hunt by Thomas Vinterberg.
Two young Romanians, Cosmina Stratan and Cristina Flutur, shared the best actress prize for their roles in Cristian Mungiu's "Beyond the Hills", about a young nun and her friend who falls victim to a deadly "exorcism".
Mungiu, who captured the Palme d'Or in 2007 for the Communist-era abortion drama 4 Years, 3 Months and 2 Days, also won this year's screenplay prize for the story that explores how badly institutions can fail the individual.
The festival's runner-up Grand Prix award went to Reality, a tragicomedy by Italy's Matteo Garrone starring a jailed former mafia hitman as a father driven mad by a quest to become a reality TV star.
Neapolitan Aniello Arena was given permission to act in the film on a day-release programme, but not to join the cast and crew on the Riviera.
Cannes veteran Ken Loach took the third place Jury Prize for his bittersweet comedy The Angel's Share, about a young offender who discovers a life-changing talent for whisky-tasting.
The 75-year-old, who took the Palme in 2006 for The Wind That Shakes the Barley about Ireland's independence struggle, was competing in Cannes for a record 11th time.
The one exception to the European line-up was Mexico's Carlos Reygadas, who took best director for the puzzling family drama Post Tenebras Lux, whose Latin title means "after darkness, light".
The Cannes jury said the film - which baffled festival-goers - had divided them as well, but its defenders won out in the end.
"It is full of the fragility of life, the vulnerability of life, full of tenderness," Andrea Arnold, British film-maker and juror, said.
Among the works overlooked, there were gangster flicks by Australia's Andrew Dominik and John Hillcoat, tales of the American South by Jeff Nichols and Lee Daniels, and a critique of capitalism from Canada's David Cronenberg.
Likewise Brazilian Walter Salles for his adaptation of Jack Kerouac's cult novel On the Road, and the Arab Spring drama After The Battle by Egypt's Yousry Nasrallah.
There were no prizes for either of two Asian directors shown here, the South Koreans Im Sang-Soo and Hong Sang-soo.
A bout of stormy weather threatened to take some of the glitz out of the event, but the 65th Cannes Film Festival still drew a galaxy of stars to its red-carpet including Nicole Kidman, Sean Penn and Brad Pitt.
The festival was also thrown on the defensive by protests over the absence of women directors in this year's line-up, prompting its veteran chairman Gilles Jacob to say organisers would look harder next year for female talent.