To unfold that interesting and dramatic period which opened with the return of Pius IX. and closed with the fall of the temporal power, it was necessary to pause and weigh the mass of publications issued concerning the epoch, besides searching among private archives and familiar correspondence and also questioning survivors. More than once I was discouraged, and felt tempted to abandon the enterprise. Only the passion for research supported me in this arduous labour, which often appeared indiscreet and was often painful, because it destroyed many a legend, dashed many a prejudice, and demolished many a romance. I was only encouraged by my desire to take a moral photograph of the Papal States and to perpetuate their memory. Rome, since September 20, 1870, has so changed as to render the reconstruction of her past most difficult, a past complicated by historical circumstances and by reason of its geography; a city not really in the centre of Italy, the political capital of a small Italian State and the religious capital of the Catholic world, girdled by a desert and marshes, almost skirting the sea, yet not a maritime city; subject to the enervating sirocco, enclosed within walls, of which two-thirds surrounded villas, vineyards, meadows, malarial cane fields and ruins. Notwithstanding the transformation caused by pulling down and rebuilding that has been so great as to cause the old city to be unrecognisable, this is as nothing compared with the moral revolution accomplished. The pyramid has been inverted. The laity, tolerated by the clemency of the ecclesiastics, has become their master; a laity, not Roman, but national. And with this new power, new systems have been imposed and needs have arisen which it seems incredible should have not been felt even before the day when Rome became the Italian capital. The old generation, of whom a few survive, is fast disappearing, and when it shall have disappeared none will know what the city was like in its intimacy, with its social classes, its public and private economy, its government, its hierarchies, its relations with the larger world, its political conspiracies and intrigues, not to mention the confusion of the temporal and spiritual powers, a fertile source of those religious and political evils which, though they were no greater than the evils of the other Italian despotisms, had in the Papal States special characteristics of their own.