"The Sweetest Song Ear Ever Heard"
Context: Byron wrote this poem in two days while he and Shelley were touring Lake Geneva, 1816. It is introduced by a sonnet on liberty beginning "Eternal Spirit of the chainless Mind!" and is written as a monologue. The historical prisoner was François de Bonnivard (1493-1570), prior of a small monastery outside Geneva. Bonnivard was imprisoned for six years because he tried to free Geneva from the control of the Duke of Savoy so that it could become a republic. His last four years were spent in a dungeon in the Castle of Chillon beside Lake Geneva ("Leman" in the poem). He was freed by the Bernese in 1536 and returned to his home, where he lived a long and useful life. The brothers described in the poem are Byron's own inventions. The line quoted refers to the song of a bird perched on the barred window of the cell. The prisoner's youngest brother has just died, and he is completely stunned–"I had no thought, no feeling–none–/ Among the stones I stood a stone" (ll. 235-6). The bird's song restores his senses, bringing life and hope. In context the lines read:
A light broke in upon my brain,–It was the carol of a bird;It ceased, and then it came again,The sweetest song ear ever heard.