Nijūichidaishū

The Nijūichidaishū (二十一代集, Collections of the Twenty-One Eras^?) are Japan's twenty one imperial collections (anthologies) of Japanese poetry written by noblemen. The following texts listed in chronological order constitute the Nijūichidaishū:

The Hachidaishū (八代集^?) are the first eight collections, in which the first three collections are the Sandaishū (三代集^?). The Sandaishū provided both the language and organizational principles for the rest of the anthologies thereafter. They are:

• Kokin Wakashū
• Gosen Wakashū
• Shūi Wakashū
• Goshūi Wakashū
• Kin'yō Wakashū
• Shika Wakashū
• Senzai Wakashū
• Shin Kokin Wakashū

The Jūsandaishū (十三代集^?) are the later thirteen collections. They are:

• Shinchokusen Wakashū
• Shokugosen Wakashū
• Shokukokin Wakashū
• Shokushūi Wakashū
• Shingosen Wakashū
• Gyokuyō Wakashū
• Shokusenzai Wakashū
• Shokugoshūi Wakashū
• Fūga Wakashū
• Shinsenzai Wakashū
• Shinshūi Wakashū
• Shingoshūi Wakashū
• Shinshokukokin Wakashū

Note that the Shin'yō Wakashū—although an imperial anthology of Japanese poetry—is not included in the list of twenty one collections.