Although the terms "border/boundary"and "frontier" are often interchangeably used in everyday conversations, international law scholars and geographers tend to employ "border/boundary" referring to a line, and "frontier" indicating a zone (Murty 1978; Prescott 1965).

Unlike the modern nation-state system, which demarcates independent states by clear borders, the Sino-centric world did not necessarily maintain clear boundaries between countries and regions.

Yezochi, inhabited by Ainu people or the islands of Hokkaido, Sakhalin and Kuril Archipelago, and the Ryukyu Islands were, thus, frontiers without clear borders between Japan and two countries: Russia and China. However, these ambiguous zones became problematic when Japan was pressured to join the modern nation-state system. Hence, during the late nineteenth century, the Meiji government attempted to clarify boundaries in the frontiers of both North and South.

The definition of the boundary was not simply a matter of diplomatic relations. Civilians also actively participated in drawing the national border in the southern frontier. This section explores two pioneer Japanese: Tashiro Antei and Nakagawa Toranosuke.

Tashiro Antei, originally from Kagoshima prefecture, was the first Japanese Main Islander to explore Yaeyama with an interest in industrial development, and made proposals on the development of Yaeyama to the government.  His research reports on the region, which underpinned his policy proposals, also had a significant impact on Yaeyama Studies of later periods.

Nakagawa Toranosuke, born in Tokushima prefecture, was the first Japanese Main Islander who conducted the first reclamation project in a large scale on Ishigaki Island. His project gave a great social and economic impact on Yaeyama Islands of that time.

Interestingly, both pioneers, who first claimed the significance of Yaeyama Islands, migrated to Taiwan soon after the Japanese victory over the Sino-Japanese War (1894-1895).