ALEXANDER IV. (Rinald0), Pope from 1254 to 1261, was a member of the family of the counts of Segni. On the death of Innocent IV. he was elected Pope at Naples on Dec. 12, 1254. He is described as a stout man, kindly, cheerful, but of no great brilliancy. He succeeded Innocent IV. as guardian of Conradin, the last of the Hohenstaufen, to whom he promised benevolent protection; but in less than a fortnight he conspired against him and bitterly opposed Conradin's uncle Manfred. Alexander ful minated with excommunication and interdict against the party of Manfred, but in vain ; nor could he enlist the kings of England and Norway in a crusade against the Hohenstaufen. Rome itself became too Ghibelline for the Pope, who withdrew to Viterbo, where he died on May 25, 1261. His pontificate was signalized by efforts to unite the Greek and Latin churches by the establish ment of the Inquisition in France, by favours to the mendicant orders, and by an attempt to organize a crusade against the Tatars. The registers of Alexander IV. are published by Bourel de la Ronciere and others in the Bibliotheque des Ecoles f rancaises d'Athenes et de Rome (Paris, 1895 et seq.) .