Byron wrote this poem in 1816, a few days after visiting Chillon. At that time he was not familiar with the true facts in the life of Bonnivard and his story contains numerous details which have no foundation in reality.
The castle of Chillon is situated on a rock in Lake Geneva, and is connected with the mainland by a bridge. It was built in 1218, and served both as a fortress and a prison.
11. Bonnivard was imprisoned for political reasons, not on account of his religion.
14. tenets. Beliefs.
25. Not historically true. Francis Bonnivard was the only one of his family who was imprisoned in Chillon.
27. seven pillars. In reality there are eight, one of which is partly built into the wall.
Gothic. A style of architecture introduced during the Middle Ages. Among other characteristics it was marked by high pointed windows and clustered pillars.
35. a marsh’s meteor lamp. The Will o’ the Wisp,—luminous gases rising from the marsh.
38. cankering. Corroding.
52. But. Except.