Hildegard of Bingen is a Doctor of the Church. She was also a writer, composer, philosopher, Christian mystic, and German Benedictine abbess.
Hildegard quickly became recognized for her immense knowledge of all things faithful, music and natural science, with knowledge of herbs and medicinal arts, despite never having any formal education and not knowing how to write. Much of her insight is believed to have been communicated by God himself through her frequent visions. At first, Hildegard did not want to make her visions public, but she would confide in her spiritual director. He passed on the knowledge to his abbot, who decided to assign a monk to document everything Hildegard saw.
You can read a great article about Hildegard at the New Yorker.