In the middle ages much of the Campagna was fertile, and peopled by an industrious peasantry. Its undulating slopes waved with abundant crops, varied and sheltered by venerable woods, which the Goths and Vandals of former centuries had spared. But incessant civil feuds proved more fatal than barbarian hordes. The Ghibelline Colonna, from their fortresses of Marino and Palestrina, watched the fitting moment to pour their armed retainers on the plain, and, crossing the Tiber, carried fire and sword, through the estates of their rivals, to the very gates of Bracciano. The Guelphic Orsini waited for revenge only till the ripened harvest had prepared for them a golden spoil in their foemen's fields. Year after year did this miserable partizan-warfare ravage those devoted lands till the peasantry by degrees were exterminated, or driven to seek a livelihood in some more tranquil spot; till of their smiling homes no stone remained upon another, except where, at long intervals, the farm buildings were turned by these men of blood into fortresses, or the tombs of the dead were desecrated into defences for the living. A soil teeming with fertility under a burning sun, and abandoned by man, ran to rank vegetation, which, gradually choking the water-courses, generated miasma. The evil, thus commenced, was augmented by cutting down the trees which shadowed the burning earth, and, not unfrequently, covered a hostile ambush. But the crowning mischief was the rash destruction of a vast forest which, extending between the Campagna and the sea, excluded the malaria that brooded over the Mediterranean coast from Leghorn to Mola di Gaeta. Once admitted, that fearful scourge took possession of the depopulated territory, which has ever since remained a puzzle to the physiologist, a mystery to the moralist, a terror to all. At no period had the feuds of the Colonna and Orsini been more virulent than during the feeble reign of Innocent, when their armed bands had more than once scoured the streets of Rome, and overawed the papal government. The Savelli, the Frangipani, and the Gaetani, those great families who, a century or two before, had been their rivals, were no longer able to cope with them, and the lesser barons of the Comarca sought protection and employment by ranging themselves as their respective partizans. To humble these rampant houses was thus the natural policy of the successors of St. Peter, and especially of Alexander VI., who soon devoted his ambition and his authority to provide temporal sovereignties for his illegitimate progeny. His ruthless proceedings, and the changes which ensued over the whole country, at length effectually quelled the lawless turbulence of these chiefs; but it was too late to remedy the ruinous havoc which their insatiate strife had occasioned. [Illustration: "DIVA JULIA" _From a bronze medal by L'Antico in the British Museum_] [Illustration: CESARE BORGIA _From a medal ca. 1500 in the British Museum_]