Compared with the area which was called Ezo where ainu lived, Wajinchi referred to the area which was the whole area of southern end of Oshima Peninsula, where Wajin (Japanese) were living.
蝦夷と呼ばれるアイヌが居住する蝦夷地に対して、もっぱら和人（日本人）が居住する渡島半島南端の一帯を指した。