Apart from their vast extent and their subject-matter--of which more in the sequel--the mosaics are of prime importance for the contribution they make to dating the villa. About its date there is controversy. Professor Biagio Pace (who excavated here in the ’30’s), relying on stylistic similarities to late (fifth century A.D.) mosaics in Ravenna and Constantinople, would date the villa in about A.D. 410, and ascribe its ownership to a rich Sicilian landed proprietor. Pace’s pupil G. V. Gentili, who was in charge of the 1950 excavations, argues, following the Norwegian archaeologist H. P. L’Orange, for an earlier date. One piece of evidence not adduced by him is conclusive in his favor. The double-apsed entrance (8) to the baths contains a spirited mosaic depicting the Circus Maximus in Rome, full of life and movement, with the chariots of the four stables, the Greens, Blues, Whites, and Reds, all represented. The Green--the Emperor’s favorite--wins, not without a collision. Down the center of the oval track runs the _spina_, or division-wall, surmounted by various monuments, including a single obelisk in the center (Fig. 13.3). Now it is known that Augustus set up an obelisk in the Circus Maximus, and that in A.D. 357 Constantius added another: therefore any representation of the Circus with only one obelisk must be earlier than 357. Pace’s late date is therefore excluded. Is there any possibility of still more precise dating? Gentili thinks there is. Beginning from the _a priori_ proposition that a complex architecturally and artistically as grand as this must be beyond the means of any private citizen, however rich, he assumes that the villa must have been built to the order of an Emperor. Which one? To answer this question he looked among the mosaics for possible portraits, and he found them in several places. For example, in the vestibule (13) between the baths and the trapezoidal peristyle (15) there is an obvious portrait study of the mistress of the villa flanked by two children, presumably her son and daughter. The son has a squint. He is represented again, with the same squint, in the northeast apse of the _frigidarium_ (9), in the room of the small hunting scene (23), and in the vestibule of Cupid and Pan (35). (The effect of the squint is achieved by setting one eye with a square tessera, the other with a triangular one.) [Illustration: FIG. 13.3 Piazza Armerina, Imperial Villa, Circus Maximus mosaic. (Dorothy MacKendrick photo)] [Illustration: FIG. 13.4 Piazza Armerina, Imperial Villa, small hunting scene, mosaic. (Pace, _Mosaici_, Fig. 30)]