It covers the poems which had been composed for about 130 years, the period after "Kokin" and "Gosen Wakashu" (Later Selected Collection of Japanese Poetry), which is equivalent to the reign of Emperor Murakami (946 - 967) to that of Emperor Shirakawa (1073 - 1087).
選歌範囲は『古今』『後撰和歌集』以後、村上天皇朝から白河朝までの約130年間である。