Upon this, Guelfo, perceiving that his adversary sought the alliance of this monarch, applied on his side to Pope Honorius II , who being at variance with the former, and hearing how the affair stood, immediately joined the cause of the Guelfs, the Emperor having already embraced that of the Ghibellines. It is thus that the apostolic see became connected with the former, and the empire with the latter faction; and it was thus that a vile hound became the origin of a deadly hatred between the two noble families. Now it happened that in the year of our dear Lord and Redeemer 1215, the same pestiferous spirit spread itself into parts of Italy, in the following manner. Messer Guido Orlando being at that time chief magistrate of Florence, there likewise resided in that city a noble and valiant cavalier of the family of Buondclmonti, one of the most distinguished houses in the state. Our young Buondelmonce having already plighted his troth to a lady of the Amidei family, the lovers were considered as betrothed, with all the solemnity usually observed on such occasions.