When first appointed auxiliary bishop of the Diocese of Honolulu in Hawaii, Joseph Anthony Ferrario became a titular bishop of the titular see of the ancient Egyptian city of Cusae.

A titular see in the Roman Catholic Church is a diocese that now exists in title only. It is led by a ceremonial titular bishop, an honorific granted on certain priests by the Pope. Bishops who do not have proper authority over an existing diocese are normally given a titular see by the Vatican. The Roman Curia maintains a regular position on titular sees. It states, "It is the custom of the apostolic see to confer on these bishops the title of one of those churches which in days past flourished with the splendor of virtue and the progress of religion, even though as a result of the changes and ravages of time they may now have lost their ancient resplendent glory." While the Vatican hopes that titular sees will one day become active dioceses once again, it realizes in most cases the chances of that happening are low.

During the historical expansion of Christianity, the Roman Catholic Church expanded its realm. However, in some areas of the world where the religion once flourished, the presence of the Roman Catholic Church has now diminished or disappeared. Local churches split off from the larger Church while others were converted to Islam. The Roman Catholic Church adopted the practice of assigning bishops to titular sees as a way of remembering those dioceses.