The mention of obliteration suggests a third cause of the comparative want of mediæval buildings in the city--the constant depredations and changes of which she has been the subject. Ever since the time of Constantine Rome has been a city of destruction, and Christians have vied with pagans, citizens with enemies, in urging on the fatal work. Her siege and capture by Robert Guiscard[344], the ally of Hildebrand against Henry the Fourth, was far more ruinous than the attacks of the Goths or Vandals: and itself yields in atrocity to the sack of Rome in A.D. 1526 by the soldiers of the Catholic king and most pious Emperor Charles the Fifth[345]. Since the days of the first barbarian invasions the Romans have gone on building with materials taken from the ancient temples, theatres, law-courts, baths and villas, stripping them of their gorgeous casings of marble, pulling down their walls for the sake of the blocks of travertine, setting up their own hovels on the top or in the midst of these majestic piles. Thus it has been with the memorials of paganism: a somewhat different cause has contributed to the disappearance of the mediæval churches. What pillage, or fanaticism, or the wanton lust of destruction did in the one case, the ostentatious zeal of modern times has done in the other. The era of the final establishment of the Popes as temporal sovereigns of the city, is also that of the supremacy of the Renaissance style in architecture. After the time of Nicholas the Fifth, the pontiff against whom, it will be remembered, the spirit of municipal freedom made its last struggle in the conspiracy of Porcaro, nothing was built in Gothic, and the prevailing enthusiasm for the antique produced a corresponding dislike to everything mediæval, a dislike conspicuous in men like Julius the Second and Leo the Tenth, from whom the grandeur of modern Rome may be said to begin. Not long after their time the great religious movement of the sixteenth century, while triumphing in the north of Europe, was in the south met and overcome by a counter-reformation in the bosom of the old church herself, and the construction or restoration of ecclesiastical buildings became again the passion of the devout[346]. No employment, whether it be called an amusement or a duty, could have been better suited to the court and aristocracy of Rome. They were indolent; wealthy, and fond of displaying their wealth; full of good taste, and anxious, especially when advancing years had chased away youth's pleasures, to be full of good works also. Popes and cardinals and the heads of the great families vied with one another in building new churches and restoring or enlarging those they found till little of the old was left; raising over them huge cupolas, substituting massive pilasters for the single-shafted columns, adorning the interior with a profusion of rare marbles, of carving and gilding, of frescoes and altar-pieces by the best masters of the sixteenth and seventeenth centuries.