Melancholia is a 2011 film written and directed by Lars von Trier, starring Kirsten Dunst, Charlotte Gainsbourg and Kiefer Sutherland. The narrative revolves around two sisters during and shortly after the wedding party of one of them, while Earth is about to collide with an approaching rogue planet. The film prominently features music from the prelude to Richard Wagner's opera Tristan und Isolde (1857–59).

Trier's initial inspiration for the film came from a depressive episode he suffered and the insight that depressed people remain calm in stressful situations. The film is a Danish production by Zentropa, with international co-producers in Sweden, France, Germany and Italy. Filming took place in Sweden.

The film premiered in May 2011 at the 64th Cannes Film Festival. Dunst received the festival's Best Actress Award for her performance.

The film begins with an introductory sequence shot in extreme slow motion, involving the main characters and images from space which introduce many visual leitmotifs of the film. A shot from the vantage point of space shows a giant planet approaching Earth; the two planets collide. The film continues in two parts, each named for one of two sisters.

Melancholia (from Greek μελαγχολία - melancholia, "sadness", literally black bile), also lugubriousness, from the Latin lugere, to mourn; moroseness, from the Latin morosus, self-willed, fastidious habit; wistfulness, from old English wist: intent, or saturnine, (see Saturn), in contemporary usage, is a mood disorder of non-specific depression, characterized by low levels of both enthusiasm and eagerness for activity.

In a modern context, "melancholy" applies only to the mental or emotional symptoms of depression or despondency; historically, "melancholia" could be physical as well as mental, and melancholic conditions were classified as such by their common cause rather than by their properties.

The name "melancholia" comes from the old medical belief of the four humors: disease or ailment being caused by an imbalance in one or other of the four basic bodily liquids, or humors. Personality types were similarly determined by the dominant humor in a particular person. According to Hippocrates, melancholia was caused by an excess of black bile, hence the name, which means 'black bile', from Ancient Greek μέλας (melas), "dark, black", + χολή (kholé), "bile"; a person whose constitution tended to have a preponderance of black bile had a melancholic disposition. See also: sanguine, phlegmatic, choleric.

2011 (MMXI) was a common year that started on a Saturday in the Gregorian calendar. It was the 2011th year of the Common Era (CE) and Anno Domini (AD) designations; the 11th year of the 3rd millennium and of the 21st century; and the 2nd of the 2010s.

The United Nations designated 2011 as the International Year of Forests and the International Year of Chemistry. It was marked by a wave of revolutions in the Arab World known as the Arab Spring, including the beginnings of several unresolved protest movements and armed conflicts.

A film, also called a movie or motion picture, is a series of still or moving images. It is produced by recording photographic images with cameras, or by creating images using animation techniques or visual effects. The process of filmmaking has developed into an art form and industry.

Films are cultural artifacts created by specific cultures, which reflect those cultures, and, in turn, affect them. Film is considered to be an important art form, a source of popular entertainment and a powerful method for educating – or indoctrinating – citizens. The visual elements of cinema give motion pictures a universal power of communication. Some films have become popular worldwide attractions by using dubbing or subtitles that translate the dialogue into the language of the viewer.

Films are made up of a series of individual images called frames. When these images are shown rapidly in succession, a viewer has the illusion that motion is occurring. The viewer cannot see the flickering between frames due to an effect known as persistence of vision, whereby the eye retains a visual image for a fraction of a second after the source has been removed. Viewers perceive motion due to a psychological effect called beta movement.

Lars von Trier (Danish pronunciation: [ˈlɑːs fʌn ˈtʁiːˀɐ]; born Lars Trier; 30 April 1956) is a Danish film director and screenwriter. He is closely associated with the Dogme 95 collective – an avant-garde filmmaking movement – although his own films have taken a variety of approaches. His work has frequently divided the critics.

Von Trier began making films at the age of eleven. Raised by a communist mother and a socialist father in an austere environment, he converted at the age of 30 to the Catholic Church. Von Trier suffers periodically from depression, as well as various fears and phobias, including an intense fear of flying. As he himself said in an interview, "Basically, I'm afraid of everything in life, except filmmaking".. His first publicly released film was an experimental short called The Orchid Gardener (1977) and his first feature film came seven years later with The Element of Crime (1984). Among many other prizes, awards and nominations, he is the recipient of the Palme d'Or, the Grand Prix, and the Prix du Jury at the Cannes Film Festival.