Emilie Juliane of Barby-Mühlingen, countess of Schwarzburg-Rudolstadt (born 16 August 1637)
The daughter of Albert Frederick, count of Barby-Mühlingen and his wife, Sophie Ursula of Oldenburg-Delmenhorst, Emilie Juliane was born in Rudolstadt, where her family had been forced to flee during the Thirty Years War.
Her parents died relatively soon after her birth, her father in 1641, her mother in 1642, leaving the little girl in the care of an aunt, Emilie of Oldenburg-Delmenhorst. The younger Emilie was well-educated, tutored especially in scripture, Latin, rhetoric, music, and poetry by Ahasuerus Fritsch, himself a noted hymnist.
In 1665, when she was twenty-eight years old, she married her cousin, Albert Anton, the count of Schwarzburg-Rudolstadt--he was Emilie of Oldenburg-Delmenhorst's son.
Emilie Juliane was an "exemplary consort" for some forty years of marriage. According to Judith Aikin, she used her inheritance to improve the economic prosperity of her husband's principality. She established schools and scholarships for students to attend those schools. She oversaw the spiritual well-being of the people in Schwarzburg and devoted herself to charitable work. She was, in short, the perfect Landesmutter ("mother of the country"). She died on 3 December 1706.
But Emilie Juliane is best remembered today for her composition of hymns, deeply influenced by her Lutheran faith. More than 600 hymns survive. Several collections were published in her lifetime, including Geistliche Lieder (Sacred Songs, 1683); Kuhlwasser in grosser Hitze des Creutzes (Cooling Water in the Great Heat of the Cross, 1685), and Tägliches Morgen- Mittags- und Abendopfer (Daily Worship for Morning, Noon, and Evening, 1685). In 1683 she also published a prayer book for women, focusing especially on pregnancy and childbirth (Spiritual Wives). Bach used Emilie Juliane's texts in his several of his cantatas (see BWV 27, 84, and 166, for example).
For the original German text and English translation of one of her hymns, "Who Knows How Near to Me Is My End!" you can click here. For information about Emilie Juliane from the Evangelical Lutheran hymnal, which includes hymns by Emilie Juliane, click here (her name is alphabetized under "Amilie").
For further detailed analysis, you may be interested in Judith P. Aikin's A Ruler's Consort in Early Modern Germany: Aemilia Juliana of Schwarzburg-Rudolstadt--the book may be expensive, but the Amazon website will let you read the very informative introduction.