Historically, they were also the clergy of the city of Rome serving the Pope as the Bishop of Rome and were assigned duties in parishes of the city. The College has no ruling power except during the sede vacante period, where its powers are still extremely limited according to the Apostolic constitution Universi Dominici Gregis. The history of the College of Cardinals as a college dates to the beginning of the 12th century when the cardinal bishops, cardinal priests, and cardinal deacons ceased acting as separate groups.
The council has its origins in the events surrounding the crowning of Henry IV as King of Germany and Holy Roman Emperor at the age of six, after the unexpected death of Henry III in 1056. Up until this point secular authorities had significant influence over who was to be appointed Pope, and the Holy Roman Emperor in particular had the special ability to appoint him. This was significant as the aims and views of the Holy Roman Emperor and the Roman Catholic Church did not always coincide. Members of what was to become known as the Gregorian Reform took advantage of the new King and his lack of power, and in 1059 declared that the election of the Pope was an affair only for the Church. This was part of a larger power struggle, named the Investiture Controversy, as the Church attempted to gain more control over their clergy, and in doing so gain more influence in the lands and governments they were appointed to. Theological implications aside, its creation represented a significant shift in the balance of power in the Early Medieval world.
The Dean of the College of Cardinals and the Sub-Dean are the president and vice-president of the college. Both are elected by and from the cardinals holding suburbicarian dioceses, but the election requires Papal confirmation. Except for presiding, the Dean has no power of governance over the cardinals, instead acting as primus inter pares.
The Secretary of State, the prefects of the Congregations of the Roman Curia, the Camerlengo of the Holy Roman Church, the Vicar General of Rome, and the Patriarchs of Venice and Lisbon, are usually Cardinals, with few, generally temporary, exceptions. The Fundamental Law of Vatican City State requires that appointments to the state's legislative body, the Pontifical Commission for Vatican City State, be cardinals.
The rules for the election of the Roman Pontiff are stated in Universi Dominici Gregis, published by Pope John Paul II on 22 February 1996. It states that cardinals over the age of 80 on the day the see becomes vacant do not have a vote in the Papal election.
Although the rules of the Conclave explicitly say the Pope need not be chosen from among the ranks of the Cardinals (in theory any unmarried Catholic male may be elected Pope), this has been the consistent practice since the election of Pope Urban VI in 1378.
Cardinals aged over 80 are indicated with an asterisk (*). Michael Michai Kitbunchu, Archbishop of Bangkok, will be the next to lose his right to participate in the conclave on January 26, 2009. The oldest living cardinal is currently Paul Augustin Mayer.
All but thirteen of the Cardinals alive at the death of Pope John Paul II were appointed by him. Three of those thirteen were under 80 years old as of the day of John Paul II's death. One of those three (Joseph Cardinal Ratzinger) has since been elected Pope as Benedict XVI, another one (Jaime Cardinal Sin) did not attend the resulting conclave for health reasons and died shortly afterwards, and the third, William Wakefield Baum, turned 80 on 21 November 2006. There are now a total of 193 cardinals of whom 116 are aged under 80.
Patriarchs of Oriental Rites