Earlier this month, New York's Timothy Cardinal Dolan wrote in his blog about taking possession of his titular church in Rome. Well if you're not familiar with that, you might want to ask: What's a titular church? And why does Cardinal Dolan have one? Here's the answer.
The first cardinals of the Catholic Church were actually the priests in Rome. For obvious reasons, they were the pope's closest advisers and elected a new pope when the Holy See became vacant. When clergy from outside of Rome were selected to be cardinals, the custom of linking them to a Roman church began. At that time, a church around Rome was known as a titulus, and someone who held property for the Universal Church was called a titular. (Titulus/titular are from the Latin meaning title.) Today, cardinals who are designated cardinal priests are given a titular church in Rome from this tradition. The cardinal gets his name and coat of arms at or near the door of the church, but in most cases has little to do with its administrative or sacramental life. In a similar way, cardinals who are cardinal bishops are given one of the Suburbicarian Sees near Rome, and cardinals who are cardinal deacons are also given a titular church called a cardinalatial deaconry. This way, where ever in the world a cardinal resides, he remains symbolically close to the pope.
The other case where the term titular church is used is with bishops who are not heads of dioceses. These bishops are known as titular bishops. Auxiliary bishops, papal nuncios, and heads of the Roman Curia are common examples. While these bishops do not function as diocesan bishops, they must still be the bishop of a church or diocese, at least symbolically. As a result, a diocese that no longer exists, called a titular see, is assigned to them. These titular dioceses will always have potential to be reinstated, although this rarely happens.
In modern times, when a diocesan see is suppressed its area is absorbed into another diocese. This could happen for organizational reasons, such as when an area's Catholic population is no longer sufficient to maintain a diocese, or if the see is moved to where the population has increased. In history, dioceses would be suppressed if the city is destroyed by disaster or war, or when conquered by non-Christians (7th century northern Africa for example). These bishops would flee to other dioceses and assist the bishop there, acting in a similar way to today's auxiliary bishops. When the helping bishop would die, there would often be a successor who would take the title of the former diocese with the hopes that it would someday be restored.
So if your diocese has an auxiliary bishop, his job is to assist the diocesan bishop in the same way another priest in the parish assists the pastor. In some way, the auxiliary bishop actually has a diocese of his own, but it has no cathedral, clergy, or laity, although it probably did at one time (and may again if it is ever restored in the future).
Since 1970, diocesan bishops whose resignations are accepted for retirement are no longer assigned titular dioceses. They are now given the title bishop emeritus of their former diocese (according to Canon 402). The same goes for a coadjutor bishop, which is a bishop designated to assist the diocesan bishop and will succeed him when he resigns or dies. Instead of being given a titular see, he is now titled coadjutor bishop of the diocese that he will eventually oversee. I'm not sure why this was changed, other than the possibility of running out of titular dioceses with the number of retired bishops is growing. If anyone knows the answer, please tell me!
I know this article is a little different from my usual stuff; I decided to let my nerdy side come out a little. The Catholic Church has many neat historical customs and traditions that the everyday Catholic may not know of, so I thought talking about one of them is good once in a while (or this could just be a total bust).
I don't know if the subject of a "titular church" will ever come up in cocktail party talk, but if it does, you'll be well prepared!