Sei Shōnagon (清少納言, c. 966–1017 or 1025) was a Japanese author, poet, and a court lady who served the Empress Teishi (Sadako) around the year 1000 during the middle Heian period.

She was the daughter of Kiyohara no Motosuke, a scholar and well-known waka poet, who worked as a provincial official.

When her court service ended she may have married Fujiwara no Muneyo, governor of Settsu province, and had a daughter, Koma no Myobu, although some evidence suggests she became a Buddhist nun.

"[5] Shōnagon is also known for her rivalry with her contemporary, writer and court lady Murasaki Shikibu, author of The Tale of Genji who served the Empress Shoshi, second consort of the Emperor Ichijō.

Shōnagon became popular through her work The Pillow Book, a collection of lists, gossip, poetry, observations and complaints written during her years in the court, a miscellaneous genre of writing known as zuihitsu.

Shōnagon's essays describe the various daily experiences and customs of the time, and the affairs of the Imperial Court in Kyoto where she lived, from a unique point of view.

First printed in the 17th century, it exists in different versions: the order of entries may have been changed by scribes with comments and passages added, edited, or deleted.

[citation needed] Shōnagon writes with apparent lightheartedness about events at court, de-emphasizing or omitting harsh realities such as Teishi's death from childbirth in 1001.

Her writing is considered witty, depicting Teishi's elegant court from a detailed, gossipy perspective.

[7] She was also known to be especially adept at recalling and quoting a classic poem to suit the occasion, even by the standards of a court in which knowledge of the poetry canon was considered an essential skill.

[7] The entries in The Pillow Book on rhetoric include advice and opinions on conversation, preaching, and letter writing.

She says that one can become distracted and inattentive when the priest is unattractive, but when he is good-looking one remains focused on his face, and as such better experiences the holiness of his sermons.

A social requirement was that the male send a poem on beautiful paper with a decorative flower or branch to the lady, and that she reply.

Another tradition has her marrying Fujiwara no Muneyo, the governor of Settsu province, after her court service ended, and having a daughter, Koma no Myobu.

Fujiwara Korechika (974–1010), Michitaka’s son, presents Empress Teishi with the paper Sei Shōnagon will use for her Pillow Book.

996 Teishi’s brothers Korechika and Takaie (979–1044) attack retired emperor Kazan; they are arrested and forced to leave the capital. ?

Governor of Ise Minamoto Tsunefusa visits Sei Shōnagon and discovers and circulates the early draft of The Pillow Book.