But it must not be forgotten that the native art had lost its best character long before the Italian influence supervened. The finest Gothic impulse was spent before the close of the thirteenth century, and the feeble spirit and florid extravagance of the Flamboyant style which now prevailed betrayed a weakened condition of the national artistic mind which made it an easy prey to the foreign innovations. Until the sixteenth century the Gothic style survived in its decadent forms. Yet in some quarters before this time an interest in the arts of antiquity was gaining foothold, and a few Italian artists had come into France and wrought some small architectural works in the neo-classic manner. But the way appears to have been opened for a more general movement in the new direction when the French upper classes began to construct fine houses adapted to the requirements of luxurious life. This movement was favoured by the changed conditions of the times. Concomitant with the cessation of feudal turmoil and the need for fortified castles was a great increase of material wealth, far exceeding that which France had enjoyed at any former time in its history. Life and property were now secure, population grew, the towns enlarged their borders, and the resources of the king and the nobles were correspondingly enlarged.[115] These conditions had found expression in architecture during the fifteenth century in such palatial houses as that of Jacques Cœur at Bourges, and the Hôtel Cluny in Paris. These houses, though retaining the irregular character of mediæval French castles, have no defences, and are abundantly lighted on all sides by large window openings. They are the forerunners of the Renaissance châteaux. To understand the early French Renaissance château it is necessary to recall the character of the feudal castle of the Middle Ages out of which it was evolved. The plan of the feudal castle was generally irregular and its outline picturesquely broken. But its irregularity and picturesqueness were not the result of any purpose on the part of its builders to produce a picturesque effect. It was a consequence of the natural conformation of the rugged site to which the building had to shape itself, of the need for defensive towers, and of the conditions of climate calling for high-pitched roofs, more or less broken by dormers and chimney-stacks. The earlier palatial residences of the open country were in many cases the older castles remodelled or enlarged, and opened, by great windows cut through their massive walls, to the light and air.[116] And although there was no longer need for such defences as would withstand the siege of a feudal army, it was still for some time necessary to provide for security against roving bands of marauders which continued to move about, and thus the surrounding fosse and the drawbridge were retained for a considerable time after the loopholes and embattled towers of the Middle Ages had become unnecessary.