Blessed Gertrude of Altenberg, daughter Saint Elizabeth of Hungary
Abbess of the Premonstratensian convent of Aldenberg, near Wetzlar, in the Diocese of Trier; born about 1227, died 13 August, 1297. She was the youngest of three children of Louis VI, margrave of Thuringia, and his wife St. Elizabeth of Hungary. Gertrude’s father died on his way to the Holy Land shortly before she was born.
She was scarcely two years old, when St. Elizabeth brought her to the convent of Aldenberg, where she afterwards became a nun. In 1248, being then only twenty-one years of old, she was elected Abbess of Aldenberg, over which she ruled forty-nine years.
With the inheritance which she received from her uncle, the Margrave of Meissen, she erected a church and a poorhouse. She took personal charge of the inmates of the poorhouse and a led a life of extreme mortification. When Urban VI published a crusade against the Saracens, Gertrude and her nuns took the cross and obliged themselves to contribute their share to the success of the crusade by prayer and acts of mortification.
In 1270 she began to observe the feast of Corpus Christi in her convent, thus becoming one of the first to introduce it into Germany. Clement VI permitted the ecclesiastical celebration of her feast to the convent of Aldenberg and granted some indulgences to those who visit her relics at that convent.
MICHAEL OTT (Catholic Encyclopedia)