Until the 13th century, the Middle Dutch language output mainly serviced the aristocratic and monastic orders, recording the traditions of chivalry and of religion, but scarcely addressed the bulk of the population. With the close of the 13th century a change appeared in Dutch literature. The Flemish and Hollandic towns began to prosper and to assert their commercial supremacy over the North Sea, and these cities won privileges amounting almost to political independence. With this liberty there arose a new sort of literary expression.