Lit.:"East of the Gate", the easternmost of five regions located on Honshuu Island which comprises of the seven prefectures of Gunma, Tochigi, Ibaraki, Saitama, Tokyo, Chiba, and Kanagawa. This is the most highly developed and industrialized region of Japan and was the heart of feudal power during the Edo Period.

During the Edo Period, the area was also called the "Kanhasshuu" (関八州), or Eight Kantou Provinces: Musashi, Sagami, Kazusa, Shimousa, Awa, Kouzuke, Shimotsuke, and Hitachi.