PALATINUS mons, or Palatium, the first mountain of Rome occupied by Romulus, and where he fixed his residence and kept his court, as did Tullus Hostilius, Augustus, and all the succeeding emperors: and hence it is that the residence of princes is called palatium. The reason of the name is variously assigned. To the east it has the Mons Cælius, to the south the Aventine, to the west the Capitoline, and to the north the Forum.—Palatinus, the surname of Apollo from this place; where Augustus built a temple to that god, adorned with porticos and a library, (Horace).