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Classical music is a term that is applied to a body of notated European music that extends back in time to the first millennium (We use the term Western to differentiate this music from the classical music from other parts of the world). From its inception, Western classical music was the music composed for the liturgy of the catholic religion to be sung in European churches and monasteries. The earliest of this music is called plainsong, or Gregorian chant. Gregorian chant consists of a single melody that is sung by a choir of nuns or monks without the accompaniment of musical instruments. Gregorian Chant dates from the 5th and 6th centuries.
During the 10th and 11th centuries, a new type of singing evolved that was based on Gregorian chant. This style was called organum. While Gregorian chant consisted of a single melodic line, two or more melodic lines were sung at once in organum. The emergence of organum was the humble beginning from which harmony (on which all Western classical music is based) sprung. Organum was the precursor of the beautiful A cappella choral music that was first composed in the 15th century by the gifted composers Jacob Obrecht (1457/8-1505), Johannes Ockeghem (c.1410-1497), and Guillaume Dufay (c.1400 1474) who are considered the greatest composers of the early renaissance period of European music.
The great 15th Century composer Josquin des Prez (c.1440-1521) (commonly called "Josquin") created a body of sacred works in a new style that would usher in the sacred music of the renaissance. This music will reach a climax of perfection and sublimity in the works of the three greatest composers of the renaissance period: Tomas Luis de Victoria (1548-1611), Giovanni Pierluigi da Palestrina (c.1525-1594), and Orlandus Lassus (Orlando di Lasso) (1532-1594).
During the beginning of the 17th Century, a completely new style of music, called baroque music, found expression in Italy. This music was more secular in nature that of the renaissance period. It largely abandoned the sublime choral style of the renaissance in favor of a more florid solo style, and instruments were added as accompaniment. Music in the new baroque style was not only composed for the church, but also for secular entertainment as well. The first great composer of the baroque era was Giovanni Gabrieli (1557-1612). His music was still largely influenced by the renaissance style; however he employed instruments in his sacred compositions written for Saint Marks Cathedral in Venice. It was a successor at Saint Marks, Claudio Monteverdi (1567-1643), who became the first great composer to completely break with the old traditions. The baroque era ended with the complete perfection of the baroque style by Johann Sebastian Bach (1685-1750).
Johann Bachs three sons Carl Philipp Emanuel Bach (1714-1788), Wilhelm Friedemann Bach (1710-1784), and Johann Christoph Friedrich Bach (1732-1795) helped usher in the classical era of Western classical music. Joseph Haydn (1732-1809) and Wolfgang Amadeus Mozart (1756-1791) perfected the classical style.
The classical era was followed by the romantic era. Ludwig von Beethoven (1770-1827) was the great innovator who broke the hold that the music of the classical era had on Europe. Beethoven--like his predecessors Monteverdi and Josquin--created a revolution in music and completely changed the prevalent style. Beethovens music, beginning with his Third Symphony, was filled with emotion and feeling that had never before been so fully expressed. His music ushered in the flowering of the romantic era of Western classical music that brought forth a tremendous body of beautiful music exuberant with feeling and emotion from many European composers. The music of the romantic era culminated in the music of Richard Wagner (1813-1883) that brought the style to absolute perfection.
During the first years of the 20th Century, the next era of music began. This era is commonly known as the modern era of Western classical music; however, this title is really no longer applicable because the era is currently coming to a close as we head into the first years of the 21st Century. We prefer to refer to the so-called modern era as the Era of Negative Music because the prevalent focus of the era was upon discordant music, negative emotions, intellectually conceived structure, and an exploitation of ugliness. The first composers who are now considered the greatest composers of the negative era were Arnold Schönberg (1874-1951), Anton Webern (1883-1945) and Alban Berg (1885-1935). These composers introduced a new music to European audiences early in the century that no longer was based on the natural harmonic laws that all great cultures on the planet have based the harmonies and melodies of their music. Dissonant chords and intervals were said to be equal (and even preferable) to concordant ones, and melodies no longer needed to be based on a harmonic musical scale. The music of these composers ushered in the negative era and gave to the world new music that could express emotions that had never before been invoked by music: emotions such as fear, anguish, hatred and terror.