For a long period after the municipal organisation of the cities of Brabant had been definitely determined, all administrative and legislative power remained in the hands of a narrow oligarchy of great capitalists, headed by the old patrician families, which from time immemorial had furnished the magistracy. One was the source of their title to distinction--the ownership of land; but the means by which the first patricians had acquired their title-deeds were not in every case the same, nor were they all of like origin. Some of them were the descendants of _ministeriales_ who, when the township was a feudal domain, had levied their lords' dues for him, and generally managed his affairs; others of yeomen of the same period, whom thrift or good fortune had enabled to purchase the freehold of the soil they tilled; others, again, were successful traders, or the sons of successful traders, who, retiring from business, had invested the wealth which commerce had given them in real property. Together they formed a class apart, distinct alike from the feudal nobility and from the general body of townsmen. They were divided into groups in each city, which bore the characteristic title of _lignages_ or clans; but it is certain that many patricians were not the direct lineal descendants of the houses whose names and arms they bore: the status of patrician was transmissible in the female line, and patrician daughters were not unfrequently given in marriage to prosperous plebeians; moreover, some of the sons of the house were only sons by adoption--the wealthy merchant of alien blood was not always refused admission to the charmed circle, though as a rule the door of matrimony was the only door open to him; and occasionally we find whole families, sometimes sections of families, forsaking their original clan to enroll themselves in another. Indeed, the great _lignages_ of Brabant, which play so large a part in the stories of her towns, were, to a certain extent, voluntary associations of aristocratic families banded together for the sake of mutual protection and help, and with a view to securing the election of their own nominees to the magistracy; and though, no doubt, a considerable number of the members of each clan traced their descent to one stock, it is certain that the ties by which they were most strongly knit together were not those of blood, but of kindred pursuits, and kindred associations and kindred political interests. It is a significant fact, as Pirenne observes, that the number of _lignages_ in each town corresponded to the number of their aldermen, and that each _lignage_ had obtained a prescriptive right of representation in the magistracy.