Joanna of Hainaut

Joanna of Hainaut (c. 1312–1374) became countess of Jülich through her marriage to William V of Jülich, celebrated in Cologne on 26 February 1324. She was the third daughter of William I the Good, Count of Hainaut, Holland and Zeeland, and a younger sister of Philippa of Hainault, queen of Edward III of England.

Her children included William II, Duke of Jülich, and Gerhard VI, Count of Berg and Ravensberg, maternal grandfather of the Duke of Cleves.