Duchess Constance of Brittany (c. 1161–1201) was a significant historical figure in medieval Europe. She was the daughter of Duke Conan IV of Brittany and Margaret of Scotland. Constance became the Duchess of Brittany in her own right after her father's death, playing a crucial role in the political landscape of the time. In 1181, Constance married King Henry II of England's son, Geoffrey, which strengthened ties between Brittany and England. After Geoffrey's death, she became the guardian of their children, including Arthur of Brittany, who would later claim the duchy. Constance's life was marked by her efforts to maintain Brittany's independence amidst external pressures.