Mendelssohn first travelled to England at the invitation of a German lord after the composer's twentieth birthday. Following his tour of England, Mendelssohn proceeded to Scotland, where he began work on his Symphony No. 3, Scottish. He was engaged on a tour of Scotland with his travelling companion Karl Klingemann when he sent a postcard to his family with the opening phrase of the overture written on it. In a note to his sister, Fanny Mendelssohn he said: "In order to make you understand how extraordinarily The Hebrides affected me, I send you the following, which came into my head there.". The cave at that time was approximately 35 feet (11 m) high and over 200 feet (61 m) deep, and contained colorful pillars of basalt.
The work was completed on 16 December 1830 and was originally entitled Die einsame Insel, or The Lonely Island. However, Mendelssohn later revised the score, completing it by 20 June 1832, and retitled the music Die Hebriden, or The Hebrides. Despite this, the title of Fingal's Cave was also used: on the orchestral parts he labelled the music The Hebrides, but on the score Mendelssohn labelled the music Fingal's Cave. The overture was premiered on 14 May 1832 in London, in a concert that also featured Mendelssohn's Overture to A Midsummer Night's Dream.
The music, though labelled as an overture, is intended to stand as a complete work. Although programme music, it does not tell a specific story and is not "about" anything; instead, the piece depicts a mood and "sets a scene", being an early example of such musical pieces. The overture consists of two primary themes; the opening notes of the overture state the theme Mendelssohn wrote while visiting the cave, and is played initially by the violas, cellos, and bassoons. This lyrical theme, suggestive of the power and stunning beauty of the cave, is intended to develop feelings of loneliness and solitude. The second theme, meanwhile, depicts movement at sea and "rolling waves".
The piece is scored for 2 flutes, 2 oboes, 2 clarinets, 2 bassoons, 2 horns, 2 trumpets, timpani and strings.
Performances of the overture typically run between 10½ and 11 minutes. The autograph manuscript of the work is held in the Bodleian Library, Oxford.