Saint Hildegard of Bingen's career in the church began early and powerfully: her investiture as a nun at age eight was not unusual, but the mystical visions which came to her in the monastery were more vivid and potent than most. As she progressed from novice to full sister to abbess (and even to founding a new religious house), Hildegard's visions and her writing continued apace. By the time she had been leader for a few years of her own community of nuns, she had already composed (in addition to several learned treatises) an extensive collection of musical and poetic compositions for the nuns' use in worship. She wrote many of these in praise of the Trinitarian beings of the godhead, and of the Blessed Virgin Mary, but she also reserved a nontrivial fraction of her compositional attention to various saints and virgin martyrs to the faith for whom she apparently paid particular devotion. In our own time, Hildegard's music for St. Ursula and the 11,000 virgins has attained popular fame, but for the "Sybil of the Rhine" in her own work, the otherwise obscure saint named Disibod occupied a prominent place. Disibod might have remained, in fact, deep in historical obscurity if it were not for Hildegard: he happened to have founded, according to tradition, the monastery that several centuries later would be led by this most prolific medieval woman.
Hildegard's O presul vere civitatis serves as a Sequence in the liturgical plan, and thus would have been sung during the Mass of the day in honor of the saint. Specifically, it would have been sung in the theologically rich part of the Mass at the center of the service of the word, after the other Biblical readings and the Gradual proper to the day, just before the Gospel lesson and the sermon. Thus, her poetical Latin text (presumably original) takes on extra liturgical weight as it describes the particularly virtuous actions of the saint who was believed to have brought the good news of the Christian faith to her corner of the Rhine valley: his leadership of the city that would become her monastery, his placing of the community before God, and his devotion to the love of Christ. Hildegard's music for the chant inhabits a relatively intimate melodic mode, frequently shifting between the powerful half-step of a Phrygian cadence and the more ascendant leaps up a fifth and continuation to the half-step upper neighbor to this aspirant pitch.