These curias are historically descended from the Roman Curiae, and they keep that name even though they now have very different functions. When the Roman Empire collapsed, many of the administrative functions previously done by the state were subsumed by the only solid institution left, which was the church. The Bishop and curia took the place of the government officials, often to the point of sitting at the same chair in the same building. The Curia therefore passed into religious hands, and afterwards changed functions many times but always keeping its traditional name, at least in those Christian denominations that keep a strong continuity with the Apostolic tradition.