Adelaide was the youngest of Megengoz and Gerberga's daughters, and she had already been sent away to learn the religious life as a canoness at Saint Ursula's in Cologne. After Gottfried's death, her mother made an unusual move: she paid a gift of land to release Adelaide from the Cologne community so she could come home and lead the new family foundation at Vilich. Adelaide was barely out of childhood when she became the first abbess. Her sister Bertrada had married a count, but their other sister Sophia would also enter monastic life as abbess of Essen and Gandersheim — a remarkable concentration of religious power in one Rhenish family.

In 987, Megengoz and Gerberga petitioned for imperial recognition, and Emperor Otto III granted it. The charter elevated Vilich to the rank of the great imperial abbeys — Gandersheim, Quedlinburg, Essen — places where royal daughters ruled small ecclesiastical states. The nuns could elect their own abbess. No outside lord could meddle without the community's consent. For a foundation on the Rhine floodplain, surrounded by the more famous archbishopric of Cologne, that legal freedom was an extraordinary gift. The original charters still exist, tucked into the state archive in Düsseldorf, paper made out a thousand years ago still legible enough to read.

Gerberga had wanted the convent to follow the strict Benedictine rule from the start, but her young daughter resisted. The community began instead as a house of canonesses — women living a religious life but able to hold private property and leave to marry. When Gerberga died in 995, Adelaide made her own decision. She shifted Vilich onto the Rule of Saint Benedict, against the wishes of several of her sisters. It was, by medieval standards, a major institutional reform, accomplished from inside by a woman in her twenties. Adelaide ran the abbey until her death in 1015, and a cult formed almost immediately around her grave. Pilgrims came. Stories spread. She was eventually canonized.

The convent lost its imperial freedom in the 13th century, slid into a less strict observance, then weathered the slow disasters that came for so many Rhineland monasteries. The Thirty Years' War brought fire and destruction; Adelaide's relics, treasured for six centuries, vanished. The church was rebuilt in 1642 and 1643. Secularization closed the convent in 1804. Through the 19th century the buildings passed from Franciscan hospital to the Cellitinnen, then to a string of charitable institutions. Wartime bombing in 1944 leveled the church. Restoration crews picked through the rubble afterward, and the modern Sankt Adelheidis-Stift, completed in 2001, now serves as a retirement home — a thousand-year-old foundation still housing women in late life, just for a different reason.

Stand in front of the church today and the layered story is right there in the stonework. There are Romanesque bones underneath, Gothic interventions, baroque restoration, twentieth-century repair. Adelaide is the patron of Bonn, and her feast day on February 5 still draws worshippers. The Heimatmuseum next door tells the family story — Megengoz, Gerberga, Gottfried, Adelaide, Sophia — a clan whose private grief and ambition produced one of the durable holy places of the Rhineland. The crusade to Bohemia that killed a young man in 977 is otherwise barely remembered. The convent his parents built in his memory has outlasted dynasties, empires, and wars.