The head of a religious institute, who is in charge of the convent, is sometimes referred to as Mother superior. She could be the head of a monastic community or a religious congregation. Superiors of independent monasteries can also be abbesses or prioresses.
The religious sister dedicates her life to God and to the service of the church. She is bound to God, the church and her community by vows or promises and is subordinate to her superior.
Hildegard of Bingen OSB (German: Hildegard von Bingen, pronounced [ˈhɪldəɡaʁt fɔn ˈbɪŋən]; Latin: Hildegardis Bingensis; c. 1098 – 17 September 1179), also known as the Sibyl of the Rhine, was a German Benedictine abbess and polymath active as a writer, composer, philosopher, mystic, visionary, and as a medical writer and practitioner during the High Middle Ages. She is one of the best-known composers of sacred monophony, as well as the most recorded in modern history. She has been considered by a number of scholars to be the founder of scientific natural history in Germany.
Hildegard's convent at Disibodenberg elected her as magistra (mother superior) in 1136. She founded the monasteries of Rupertsberg in 1150 and Eibingen in 1165. Hildegard wrote theological, botanical, and medicinal works, as well as letters, hymns, and antiphons for the liturgy. She wrote poems, and supervised miniature illuminations in the Rupertsberg manuscript of her first work, Scivias. There are more surviving chants by Hildegard than by any other composer from the entire Middle Ages, and she is one of the few known composers to have written both the music and the words. One of her works, the Ordo Virtutum, is an early example of liturgical drama and arguably the oldest surviving morality play. She is noted for the invention of a constructed language known as Lingua Ignota.