§ 97.1. =The Roman College of Cardinals.=--All the clergy attached to one particular church were called _Clerici cardinales_ down to the 11th century. But after Leo IX. had reformed and re-organized the Roman clergy, and especially after Nicholas II. in A.D. 1059 had transferred the right of papal election to the Roman cardinals, _i.e._ the seven bishops of the Roman metropolitan dioceses and to the presbyters and deacons of the principal churches of Rome, the title of cardinal was given to them at first by way of eminence and very soon exclusively. It was not till the 13th century that it became usual to give to foreign prelates the rank of Roman cardinal priests as a mark of distinction. Under the name of the holy college the cardinals, as the spiritual dignitaries most nearly associated with the pope, formed his ecclesiastical and civil council, and were also as such entrusted with the highest offices of state in the papal domains. Innocent IV. at Lyons in A.D. 1245 gave to them as a distinction the red hat; Boniface VIII. in A.D. 1297 gave them the purple mantle that indicated princely rank. To these Paul II. in A.D. 1464 added the right of riding the white palfrey with red cloth and golden bridle; and finally, Urban VIII. in A.D. 1630 gave them the title “Eminence.” Sixtus V. in A.D. 1586 fixed their number at seventy, after the pattern of the elders of Israel, Exod. xxiv. 1, and the seventy disciples of Jesus, Luke x. 1. The popes, however, took care to keep a greater or less number of places vacant, so that they might have opportunities of showing favour and bestowing gifts when necessary. The cardinals were chosen in accordance with the arbitrary will of the individual pope, who nominated them by presenting them with the red hat, and installed them into their high position by the ceremony of closing and opening the mantle. From the time of Eugenius IV., A.D. 1431, the college of cardinals put every newly elected pope under a solemn oath to maintain the rights and privileges of the cardinals and not to come to any serious and important resolution without their advice and approval.