Certain patterns emerged to govern the conduct of relations among the states of the Spring and Autumn period of ancient China. These patterns constituted a rudimentary system of interstate or international law based on the model of feudalism established under the Western Zhou. The norms of interstate relations during the Spring and Autumn period was one of the earliest systems of interstate relations and international law in the world. It was of importance in the early cultural and political development of China, allowing greater ease in maintaining relations, and facilitating the flow of trade and information. There was a growing body of customary international law which developed as contacts and commerce increased, a number of treaties were signed, and appeal was frequently made to rules set up within the leagues of states. A great many of the canons of interstate law concerned diplomacy among the states.