In the first decade of the twelfth century, a little girl from the Rhineland town of Bermersheim, near Mainz, was offered by her parents as a sacrifice to God. Her name was Hildegard; her parents were Hildebert and Mechthild, a pious knight and his pious, well-born wife. Hildegard was eight years old when she was left for life with an anchorite named Jutta von Sponheim, who lived alone in a cell attached to the abbey church of Saint Disibod. Her childhood cut so cruelly short, Hildegard was destined to become one of the most important women of her age.

In her teens, Hildegard made her formal profession, a ceremony parallel to the Christian marriage ceremony, in which the candidate publicly committed herself for life to her monastic vows. By this point, with perhaps a dozen women and girls taking up residence at Disibodenberg, as the abbey was called, the anchorite's severe cell had become the abbess's attractive office, and its door most often have swung open to allow Jutta's spiritual daughters to receive instruction and encouragement.

In 1136, the year Hildegard turned thirty-eight, the old abbess breathed her last. Her nuns, in strictly democratic ballot, elected Hildegard as the obvious choice to succeed the foundress. In her new position, which gave her immediate regional importance and would soon bring her pan-European fame, the young abbess began a correspondence so wide-ranging as to become one of the most important sources of our information on the twelfth century. The collection— nearly four hundred of Hildegard's letters, along with many of the letters of her correspondents—is a unique medieval survival. Given her duties as abbess and the demands made on her as a result of her growing reputation, Hildegard could never have accomplished such a feat without the help of a devoted secretary. In the monk Volmar, who had served earlier as librarian and tutor to the child Hildegard, she was blessed with the perfect assistant, hardworking, detail-oriented, self-effacing, intelligent, discerning, loyal as a dog, someone who could anticipate her needs before she articulated them—what every abbess needs.

Near the middle of the century, Hildegard was inspired to leave Disibodenherg with Volmar and her nuns to establish a new foundation. Though it was true that her increasing fame had attracted more female postulants than Disibodenberg could appropriately house, not everyone was pleased. Kuno, the abbot of Disibodenherg, knew she had no right to leave without his blessing, which he steadfastly refused to bestow. After all, Hildegard and her nuns had attracted a steady stream of pilgrims; her departure would surely entail a drop in revenues. Quite a few of the nuns fought Hildegard's plan tooth and nail: they did not look forward to taking leave of Disibodenberg's comfortable cloisters or hazarding the sometimes perilous crossing of a great river and the subsequent rigors of homesteading in the desolate wilds of Bingen. whither their untried abbess meant to convey them. But Hildegard saw clearly the necessity of separating her nuns—financially and spiritually but also, most important, juridicallv—from the monks. In their new convent the sisters would be independent of male rule, and their abbess would no longer report to anyone.

In 1141, more than ten years before, Hildegard had received at Disibodenherg a call that would shape the rest of her life and the lives of countless others, a call to "cry out and write" what she saw. From earliest childhood, she tells us, she saw things that others did not see: human and animal forms, sometimes those of angels or demons, enclosed within symbolic landscapes or within elaborate, if schematic, architectonics. All these figures—and in fact the whole of Hildegard's constant vision—were bathed in uncanny light, a luminosity that she came to call "the reflection of the living Light.".

At five, for instance, as she and her nursemaid observed a cow, she could see the fetus inside the cow's belly and predicted—accurately, to the nurse's subsequent astonishment—the color of the calf-to-be. She soon learned to keep her visions to herself confiding them only to Jutta, who confided them to Volmar. She felt no impulse to share them further till she was called to do so in her early forties, when she'd already been abbess for six years. The form her revelations took was characteristic of Hildegard—not the sloppy, spontaneous babblings of the typical illiterate seer but a lengthy convoluted text, Scivias, composed by Hildegard with excruciating exactitude over ten years and copyedited with bulldog tenacity by Volmar, whose Latin was better than hers.

In 1147, prior to her move across the river, she sent her incomplete Scivias to Bernard of Clairvaux, a Frenchman of the Cistercians, a monastic order of strictly observant Benedictines who were spearheading ecclesiastical reform. He was the most famous religious figure of his day, and Hildegard was looking for confirmation. In her covering letter she abases herself in the approved manner ("Wretched, and indeed more than wretched in my womanly condition") and hallows Bernard ("Steadfast and gentle father"); she even recounts her vision of Bernard as 'a man looking into the sun, bold and unafraid.” Bernard was, in fact, one of the most aggressive players of his time, always on the hunt for heretics, allowing no quarter to anyone who disagreed with him, preacher of the disastrous Second Crusade. No admirer of women, he was famous for his bons mots: "It is more difficult to live with a woman without [moral] danger than to raise the dead to life."

Bernard was also mentor to the current pope, Eugene III, who (as luck would have it) was himself in receipt of a copy of the incomplete Scivias. Kuno, abbot of Disihodenherg, had sent this copy to his own archbishop, Heinrich of Mainz, humbly begging Heinrich to judge its orthodoxy. Heinrich handed the work to Eugene, who was just then presiding over a synod at nearby Trier, the old Romano-Germanic hub, still graced with impressive Roman stoneworks as well as elegant new medieval buildings, bankrolled by the synod's hosts, the increasingly prosperous merchants of Trier.

Eugene read out passages from the lionized local abbess's work to the assembled bishops. One can only imagine the supercilious expressions on the well-fed faces of the costumed hierophants—till a gaunt, starkly robed monk, Bernard, attending the synod as papal theologian, stepped forward meekly to one-up them all, explaining that he had already been sent his copy, had read it diligently, and approved of every word the woman wrote. Hildegard, approaching fifty, became instantly famous, receiving papal approbation as a genuinely orthodox but prophetic seer.

Hildegard was launched on a new career as preacher to the people of her time, the only woman allowed to break the supposedly absolute New Testament proscription, contained in the First Letter to Timothy that "no woman is to teach or to have authority over a man." The exception made for Hildegard is evidence not only of her universal celebrity but of the quirky singularities of medieval life, It is seldom possible to say of the medievals that they always did one thing and never another; they were marvelously inconsistent. Not only does a woman preach; a cloistered nun, once offered to God as a solitary, travels from town to town—by boat, by horse, on foot, probably by litter— talking to everyone.

Despite her continuing publicity, Hildegard remained in important ways a very private person—and an artist of markedly individual spirit in a time when individuality was just beginning to show its face again in society after centuries of banishment. Her music is chant, largely unaccompanied, as was most church music of her tune, but quite possibly polyphonic (despite the fact that the manuscripts give us only the line of melody), since polyphony appearing as early as the ninth century had become the musical dessert of Hildegard's day. But no one else was singing songs that sounded like what the nuns of Bingen were singing. The melody lines of Hildegard's compositions alternate between moments of rigid control and those of floridly swooping excess, as the melody threatens to abandon pattern altogether and jump the tracks. The rhythms are as far from ti-dum, ti-dum as can be imagined, full of wild irregularity yet coming together in an intelligible whole. The words, also by Hildegard, are one with her music, obedient to no known rules, loosely metrical but unbound, the Western world's first free verse. As one follows her kaleidoscopic patterns, melting into chaos, melting into new patterns, one cannot but think of the abandoned sensuality of jazz.

In the twelfth century virginity had its pleasures. So did noble birth. Without both these ancient social institutions, we would never have heard of Hildegard. Thank God her parents didn't marry her off and keep her mute for the ages.