In the early days the art of painting, like all the other arts and crafts, was cultivated only in the cloister, and to the end of the eleven hundreds it was submitted almost entirely to the control of the religious orders. Not that the monks were the only artists and the only artisans: attached to all the great abbeys, and even to some of the smaller monasteries, and to more than one collegiate church, were vast bodies of lay craftsmen--so vast that their numbers were often reckoned by hundreds, sometimes by thousands, as we have documentary evidence to show: these men lived under the protection of the monks, had received their instruction at their hands, worked for them and with them, on the monastic domain, and also, but under strict regulations, for outsiders as well. Presently a change came, brought about by the rise of the cities: the monastery then ceased to be the only place where art could be cultivated in peace, and a vast immigration of artists to these new havens of refuge was the consequence. The new-comers, too feeble to stand alone, and not at first sufficiently numerous to be able to form distinct corporations, solved the difficulty by affiliating themselves to existing trade companies, sculptors joining hands with masons, and painters with glaziers and saddlers. A few abbeys here and there continued for a while to maintain their art schools and their lay art-workers, but their numbers gradually diminished, and by the close of the twelve hundreds there were no lay craftsmen of any kind outside the city walls. By this time the city artists were sufficiently numerous to be able to combine in distinct corporations. The first institution of this kind of which we have any record was the Guild of Saint Luke at Ghent, which was founded by the art-workers of that city as early as 1337; four years later the painters of Tournai followed their example; the guild of Saint Luke, at Louvain, was founded before 1350, that of Bruges in 1351, of Antwerp in 1382, and by the opening of the fourteen hundreds almost every city in the Netherlands possessed its painters' guild.