Koryŏ, much more than the preceding Silla kingdom and the ensuing Chosŏn kingdom, was a vibrant society that embraced pluralism. From its founding that saw the unification under one state of the immediately preceding Three Kingdoms to its support of many competing philosophical beliefs, Koryŏ flourished within a truly international milieu. The start of the tenth century, witnessing the collapse of the Tang dynasty, opened much of East Asia to change, which Koryŏ readily accepted. As a maritime state, that received new ideas and goods from around the region, international trade flourished and rigid social barriers were relaxed. Koryŏ exemplified the idea of unity within variety.