After the Joseon Dynasty succeeded the Goryeo Dynasty, calligraphy underwent new changes. The calligraphy during the Goryeo Dynasty was a combination of Buddhist and literary culture. In the early stage, the form of written characters accepted the styles of Wang Xizhi, Ouyang Xun, and Yan Zhenqing. Subsequently, the styles of Mi Fu and Su Shi were also included. The focus was placed on how to express the concept. In the late stage of the Goryeo Kingdom, the Songxue (Pine Snow) style dominated the calligraphic world. Created by Zhao Mengfu of the Yuan Dynasty, the Songxue style was highly praised and valued by the Goryeo royal family and later accepted and embraced by the new Joseon Kingdom. During the late period of the Goryeo Dynasty, a lot of problems occurred due to the interferences of Buddhism. Therefore, the Joseon Kingdom advocated Confucianism while rejecting Buddhism; Buddhist monks were not allowed to enter the four grand gates of the palace. Paying supreme tribute to Confucianism, the Joseon Dynasty placed great emphasis on calligraphy. Scholars, politicians, and Yangban literati and officials were all very good at calligraphy. Introduced in the late period of the Goryeo Kingdom, Zhao Mengfu’s calligraphy was popular with the Joseon royal family; kings like Prince Anpyung and Seongjong were representative followers of this style. For the Joseon Kingdom, calligraphy was a crystal of knowledge and art. During the Joseon Dynasty, the status of its kings was sacred and inviolable, in possession of legislative, executive, and judicial powers. The royal calligraphy was the standard brushwork for anyone learning this art. Therefore, the royal calligraphic works were the outline of the calligraphic history of Joseon kings. In such an atmosphere, all the twenty-seven kings of the Joseon Dynasty (lasting 519 years) were experts at calligraphy. This paper aims to explore the characteristics of the calligraphic works of the Joseon kings from Taejo to Gojong, the husband of Empress Myeongseong, during the Japanese invasion.