Byronic heroes were based off of Lord Byron's epic poem _Child Harold's Pilgrimage_. According to Lord Macaulay in Rupert Christiansen's _Romantic Affinities: Portraits From an Age, 1780- 1830_ , this is a description:
> A man proud, moody, cynical, with defiance on his brow, and misery in his heart, a scorner of his kind, implacable in revenge, yet capable of deep and strong affection.
Lord Byron later wrote other works with heroes of a similar mold and his influence was seen during the Romantic movement and lasts through to modern works as well (ie the Phantom in _Phantom of the Opera_ )