"The Book of the Duchess" is a poem written by Geoffrey Chaucer in the late 14th century. It is considered one of his early works and is an elegy that mourns the death of Blanche of Lancaster, the wife of John of Gaunt. The poem explores themes of love, loss, and the nature of dreams. The narrative follows a narrator who falls asleep and dreams of a conversation with a grieving knight. The knight laments the loss of his beloved, reflecting on the pain of separation. Through this dream, Chaucer delves into the complexities of grief and the enduring impact of love.