An evil baron who served King Mark of Cornwall.

He knew of the affair between Tristan (Tristram) and Isolde, and he conspired with two other barons to expose it to Mark.

For a long time, Mark wavered between believing the barons and believing Tristan - and alternately banishing from his court one or the other. Finally, while laying another trap for the lovers, Denoalen was attacked and slain by Tristan.