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Hildegard of Bingen  (German: Hildegard von Bingen; Latin: Hildegardis Bingensis; 1098 - 17 September 1179), also known as Saint Hildegard and Sibyl of the Rhine, was a German Benedictine abbess, writer, composer, philosopher, Christian mystic, visionary, and polymath. She is considered to be the founder of scientific natural history in Germany. Hildegard was elected magistra by her fellow nuns in 1136; she founded the monasteries of Rupertsberg in 1150 and Eibingen in 1165. One of her works as a composer, the Ordo Virtutum, is an early example of liturgical drama and arguably the oldest surviving morality play.

Attention in recent decades to women of the medieval Church has led to a great deal of popular interest in Hildegard's music. In addition to the Ordo Virtutum, sixty-nine musical compositions, each with its own original poetic text, survive, and at least four other texts are known, though their musical notation has been lost. This is one of the largest repertoires among medieval composers.  One of her better known works, Ordo Virtutum (Play of the Virtues), is a morality play. It is uncertain when some of Hildegard's compositions were composed, though the Ordo Virtutum is thought to have been composed as early as 1151. The morality play consists of monophonic melodies for the Anima (human soul) and 16 Virtues. There is also one speaking part for the Devil. Scholars assert that the role of the Devil would have been played by Volmar, while Hildegard's nuns would have played the parts of Anima and the Virtues.  In addition to the Ordo Virtutum, Hildegard composed many liturgical songs that were collected into a cycle called the Symphonia armoniae celestium revelationum. The songs from the Symphonia are set to Hildegard's own text and range from antiphons, hymns, and sequences, to responsories. Her music is described as monophonic, that is, consisting of exactly one melodic line. Its style is characterized by soaring melodies that can push the boundaries of the more staid ranges of traditional Gregorian chant. Though Hildegard's music is often thought to stand outside the normal practices of monophonic monastic chant, current researchers are also exploring ways in which it may be viewed in comparison with her contemporaries, such as Hermannus Contractus. Another feature of Hildegard's music that both reflects twelfth-century evolutions of chant and pushes those evolutions further is that it is highly melismatic, often with recurrent melodic units. Scholars such as Margot Fassler, Marianne Richert Pfau, and Beverly Lomer also note the intimate relationship between music and text in Hildegard's compositions, whose rhetorical features are often more distinct than is common in twelfth-century chant. As with all medieval chant notation, Hildegard's music lacks any indication of tempo or rhythm; the surviving manuscripts employ late German style notation, which uses very ornamental neumes. The reverence for the Virgin Mary reflected in music shows how deeply influenced and inspired Hildegard of Bingen and her community were by the Virgin Mary and the saints.  The definition of viriditas or "greenness" is an earthly expression of the heavenly in an integrity that overcomes dualisms. This greenness or power of life appears frequently in Hildegard's works.  Despite Hildegard's self-professed view that her compositions have as object the praise of God, one scholar has asserted that Hildegard made a close association between music and the female body in her musical compositions. According to him, the poetry and music of Hildegard's Symphonia would therefore be concerned with the anatomy of female desire thus described as Sapphonic, or pertaining to Sappho, connecting her to a history of female rhetoricians.

What else did she do
Scholars such as Margot Fassler, Marianne Richert Pfau, and Beverly Lomer also note the intimate relationship between music and text in Hildegard's compositions,