外東北
The Far Eastern Republic consisted of four provinces of the former Russian empire—Trans-Baikal, Amur, the Maritime Province, and the northern half of Sakhalin island. Primarily, it represented the boundaries of the regions of Transbaikal and Outer Manchuria. The frontiers of the short-lived nation followed the western coastline of Lake Baikal along the northern borders of Mongolia and Manchuria to the Sea of Japan and the Sea of Okhotsk.