The purpose of this study is to examine the historical and ideological trends and context from the Goryeo Dynasty to the early Joseon Dynasty through the change of index words related to a ritual for rain(Giwooje). Therefore, this study aims to examine the use of DB in historical and ideological research and the possibility of new research. The change from the Goryeo Dynasty to the Joseon Dynasty can be regarded as a change from Buddhism to Neo-Confucianism in a historical and ideological way, and from the pluralistic ideological landscape to the unity-oriented ideological landscape, going beyond a simple dynasty change. The related index term is an index word that is expressed together in the search results when the entire historical records are searched with the index word. In general, the index terms related to a ritual for rain are composed of words derived from not only a combination of three letters๏ผโGi (praying, ็ฅ)โ, โDo(wishing, ็ฆฑ)โ, and โWoo (ritual for rain, ้ฉ)โ, but also a combination with other letters. Each of these three letters represents an act related to faith and the form of performing a ritual for rain. In the Goryeo Dynasty, โGiโ and โDoโ tended to be expressed together with related index words about folk beliefs or Buddhism. From the Goryeo Dynasty to the early Joseon Dynasty, โGi โ and โDoโ tended to be used much more often than โWooโ. However, โWooโ is strongly connected with Confucianism. In China, โWooโ was used in commination with Confucian political philosophy since shamanism was accepted by the state, and a similar case was found in the Goryeo Dynasty. However, in Goryeo, folk beliefs, or Buddhist rituals for rain were held together with Woosa (้ฉ็ฅ). Although โWooโ has a strong connection with Confucian political philosophy, it can be a result of reflecting the pluralistic ideological landscape of the Goryeo Dynasty. Nonthenless, โWooโ was found to be increasingly distanced from folk beliefs and Buddhism after the founding of the Joseon Dynasty. This suggests that it is related to a phenomenon where Neo-Confucianism was gradually deepening and accordingly ideologies other than Neo-Confucianism were excluded from national rituals.