In late 1367, Zhu Yuanzhang declared war on the Mongols and dispatched messengers to deliver a declaration to the people of the North China Plain. Zhu's declaration, entitled "Yu zhongyuan xi" (〈諭中原檄〉), was included in the "Xu zizhi tongjian gangmu" (《續資治通鑑綱目》) by Ming officials roughly a century later. This officially sanctioned edition of Zhu’s declaration, which differed from the original one, reflected changes in the perspectives on barbarians and dynastic legitimacy. These changes can be traced to the Tumu Crisis of 1449 and the politics of the Chenghua era (1465-1487), when mainstream thinking gradually shifted toward the view that fundamental distinctions did exist between Chinese and barbarians. The revised version of the "Yu zhongyuan xi" influenced not only later generations' views of barbarians, but also later Ming perspectives on the history of the founding of the Ming dynasty and its legitimacy. By examining various editions of the "Yu zhongyuan xi", this article traces important changes in perspectives on barbarians and dynastic legitimacy in the Ming dynasty.