Curia (Catholic Church)
In Roman Catholicism, a curia consists of a group of officials who assist in the governance of a particular Church. These curias range from the relatively simple diocesan curia, to the larger patriarchal curias, to the Roman Curia, which is the central government of the Catholic Church. It is often made up of reactionaries who serve as a check to liberal reforms.
Other bodies, such as religious institutes, may also have curias. For example, the Legion of Mary has a rank called the Curia. It stands above the Praesidium but below the Regia. The Curia is responsible for several Praesidia.
All of these have now very different functions from the Curia in Roman times, but they keep the name since they are historically descended from it. In other words, when the Roman Empire collapsed, many of the administrative functions previously done by the state where subsumed by the only solid institution left, which was the church. The Bishop and its clergy basically took the place of the officials that the government used to send, to the point of actually sitting at the same chair in the same building. So the Curia passed in religious hands, and afterwards changed functions many times but always keeping its traditional name, at least in those Christian denominations that still keep a strong continuity with the Apostolic tradition.
This diocesan curia includes the vicar general, who is normally also the moderator of the curia, any episcopal vicars, the chancellor of the curia, vice-chancellors and notaries, and a finance officer and financial council. The bishop may also add other officials of his choice.
Patriarchates and Major Archiepiscopates of the Eastern Catholic Churches have an assembly called the Patriarchal Curia, which assists the patriarch or major archbishop in administering the sui juris church. The patriarchal curia is distinct from the diocesan or eparchal curia of the patriarch or major archbishop's diocese or eparchy.
The patriarchal curia consists of the permanent synod of the Church, the chancellor, assistant chancellor, and notaries, the patriarchal finance officer, the patriarchal liturgical commission and other patriarchal commissions, and the patriarchal tribunal. Up to three bishops may be elected specifically to serve in the patriarchal curia.
The Holy See retains an organ of administration called the Roman Curia, which assists the Pope in governing the Catholic Church. The Roman Curia includes the Secretariat of State, the Curial Congregations, the Pontifical Councils, Pontifical Commissions, the tribunals, and other offices.