Complex sentence: The Treaty of Shimoda left Sakhalin territory without well defined borders which arise incidents between Russian and Japanese settlers, to remedy about this situation the Japanese gouvernment sent an embassador, Takeaki Enoboto to St Petersburg to define Sakhalin territory clearly.
Split into simpler sentences: The Treaty of Shimoda left Sakhalin territory without well defined borders, which led to incidents between Russian and Japanese settlers. In order to remedy this situation the Japanese government sent an ambassador, Takeaki Enoboto to St Petersburg to define Sakhalin territory clearly.