Although intensive wet-rice agriculture was not indigenous to either Japan or Thailand before theYayoi Period (c. 300 BC) in Japan and approximately 1000 BC in Thailand, it has become the dominant crop and staple food of the two nations. Throughout their history, the understandings of self-hood, nature, and civilization have been constructed around this intense and specialized agriculture. In addition, rituals which involve rice, such as Onnamesai in Japan and offerings to Mae Phosop (the rice goddess) in Thailand, have been crucial to the understanding of the relationship between humans and rice. Furthermore, the rise of the nations, through taxes and nationalism, has also contributed to the understandings of humans in relation to rice. This comparative anthropological study examines the similarities and differences in the adaptation of this intensive wet-rice agro-culture by further exploring the future viability of these two nations’ rice cultures.