 From its beginning near Nanjing, the school expanded to the north after laws passed in 504 and 517 forced several masters of the school to go into exile.Ironically this expulsion helped spread the movement to the north, and did little to weaken the schools organization in the south.The Daoist encyclopedia published under the patronage of the Emperor Wu of the Northern Zhou (561-578) placed a great deal of importance on the Shangqing texts.