The date is unknown. It is quite possible that William was never canonized as the official canonization process was not in place at the time of his death. He could have been elevated to sainthood by popular acclamation and approval of a local bishop.
Pope Alexander III - William is not included in the list of saints canonized by Pope Alexander III nor does the Patron Saint Index list a canonization date for him.
Yes, Saint William of Vercelli is recognized as a patron saint of the city of Vercelli in Italy, as well as of courtiers, exiles, and people seeking to live a reclusive life.
St. William of Vercelli is the patron saint of people suffering from mental illness, as well as against epidemics and headache.
William of Bourges is not a patron saint.
Yes, Saint William of Rochester is recognized as a patron saint of adopted children, foster children, and parents who have lost children.
Saint William is the patron saint of adopted children, people rejected by religious orders, and the University of Paris.
Saint Thomas More, Saint Clotilde & Saint William of Rochester are the Patron Saints of Adoption. Interestingly, Saint William of Rochester is solely dedicated to the patronage of Adopted Children, and no other areas of life. St. Joseph is the patron saint of families.
St. Liam is the patron saint of shepherds and the protection of livestock. He is also known as the patron saint of asthma sufferers.
The Patron Saint Inex lists no patron saints of bears.
Saint Lillian is not a patron saint as per the Patron Saint Index.
As per the Patron Saint Index, there is no patron saint of wrestlers. However, Saint Sebastian is the patron saint of all athletics and athletes.
A patron saint is supposed to be a protector in the Catholic religion. Patron Saint Angelico is the patron saint of artists. A patron saint is a protector of life.
Saint David is not a patron saint of England. He is the patron saint of Wales.
As per the Patron Saint Index, Saint Cedd is not a patron saint at this time.