Background
He was a son of Lorenz of Werle-Güstrow and his wife Matilda of Werle-Goldberg. After the death of his father Lorenz in 1393 or 1394, William"s older brother Balthasar ruled Werle-Güstrow alone until William became co-regent in 1418.
He was a son of Lorenz of Werle-Güstrow and his wife Matilda of Werle-Goldberg. After the death of his father Lorenz in 1393 or 1394, William"s older brother Balthasar ruled Werle-Güstrow alone until William became co-regent in 1418.
After 1426, he called himself "Prince of the Wends". When Balthasar died on 5 April 1421, William became the sole ruler of Werle-Güstrow. When Christopher of Werle-Waren died in 1425, he became ruler of all of Werle.
After 1426, he styled himself "Prince of the Wends, Lord of Güstrow, Waren and Werle".