After achieving the unification of all under Heaven, the early Yuan rulers began to reform the political space of the Southern Song capital. The evolution of their policies was closely related to the ruling situation in Jiangnan. After the Yuan army captured Lin’an, ritualistic buildings with strong overtones of imperial power within and outside the city were gradually abandoned or transformed; out of consideration for the political impact, certain protective measures were taken. Due to Kublai Khan’s apprehensions that the situation in Jiangnan would worsen, as well as Sangha’s administration, the transformation tended to be radical: The imperial palace, imperial Daoist temples, Circular Mound Altar of the southern suburbs, the mausoleums of the emperors and empresses, and so on were forcibly transformed into Buddhist temples, sparking violent unrest in Jiangnan society. The Yuan court later adjusted the relevant measures, assigning to Hangzhou the status of a provincial capital, respecting local cultural traditions, and building government offices, ancestral shrines, gate towers, and so on in accord with the Confucian code of etiquette. At the turn of the Yuan and Ming dynasties, the historical facts associated with the transformation of Hangzhou in the early Yuan Dynasty had gradually become obscured, and many mystical legends were later derived therefrom, becoming an important historical reference for governance of Jiangnan by the rulers of later generations.