"Dies Irae" (Day of Wrath) is a thirteenth century Latin hymn thought to be written by Thomas of Celano (1200 – c. 1265). It is a medieval Latin poem characterized by its accentual stress and its rhymed lines. The metre is trochaic. The poem describes the day of judgment, the last trumpet summoning souls before the throne of God, where the saved will be delivered and the unsaved cast into eternal flames.

The hymn is best known from its use as a sequence in the Roman Catholic Requiem mass. It was removed from the ordinary form of the Roman Rite mass in the liturgical reform of 1969–1970, but was retained as a hymn of the Divine Office. It can still be heard in the 1962 form of the mass. An English version is found in various Anglican Communion missals.

Those familiar with musical settings of the Requiem Mass—such as those by Mozart or Verdi—will be aware of the important place "Dies Iræ" held in the liturgy.

It remained as the sequence for the Requiem Mass in the Roman Missal of 1962 (the last edition before the Second Vatican Council) and so is still heard in churches where the Tridentine Latin liturgy is celebrated.

Dies is a surname, and may refer to:

Claudio Abbado, Cavaliere di Gran Croce OMRI (Italian pronunciation: [ˈklaudio abˈbaːdo]; born June 26, 1933), is an Italian conductor. He has served as music director of the La Scala opera house in Milan, principal conductor of the London Symphony Orchestra, principal guest conductor of the Chicago Symphony Orchestra, music director of the Vienna State Opera, and principal conductor of the Berlin Philharmonic orchestra from 1989 to 2002, when he retired from the position for health reasons.

Born in Milan, Italy, Abbado is the son of the violinist and composer Michelangelo Abbado, who was his first piano teacher, and the brother of musician Marcello Abbado. After studying piano at the Milan Conservatory, in 1955 Claudio Abbado studied conducting with Hans Swarowsky at the Vienna Academy of Music. In 1958 he won the international Koussevitsky Competition for conductors, which resulted in a number of operatic conducting engagements in Italy, and in 1963 he won the Dimitri Mitropoulos Prize for conductors, allowing him to work for five months with the New York Philharmonic.

Karl William Pamp Jenkins, CBE (born 17 February 1944) is a Welsh musician and composer.

Jenkins was born and raised in the Gower village of Penclawdd, in the county of Swansea, South Wales. His father, who was a local schoolteacher, chapel organist and choirmaster, gave him his initial musical instruction. Karl Jenkins attended Gowerton Grammar School.

Jenkins began his musical career as an oboist in the National Youth Orchestra of Wales. He went on to study music at Cardiff University, and then commenced postgraduate studies in London at the Royal Academy of Music, where he also met his wife and musical collaborator, Carol Barratt. He studied with Alun Hoddinott.

For the bulk of his early career Jenkins was known as a jazz and jazz-rock musician, playing baritone and soprano saxophones, keyboards and oboe, an unusual instrument in a jazz context. He joined jazz composer Graham Collier's group and later co-founded the jazz-rock group Nucleus, which won first prize at the Montreux Jazz Festival in 1970.