Speed was an innovator. His mythological subjects combine tradition with modernity, presenting romantic themes in a bold style that alludes to contemporary graphics and a fledging world of commercial imagery.

The artist trained as an architect, but a shift of focus led to his studying at the Royal Academy schools. He exhibited twenty works at the Academy 1893-1904, and was the subject of a seminal exhibition at the Fine Art Society in 1938.

'The Vale of Leutha' features in William Blake's epic poem, Visions of the Daughters of Albion (1793). Speed depicts the metaphysical ponderings of 'the soft soul of America, Oothoon' who 'wander'd in woe':

Along the vales of Leutha, seeking flowers to comfort her;
And thus she spoke to the bright Marygold of Leutha's vale:
'Art thou a flower? art thou a nymph? I see thee now a flower,
Now a nymph! I dare not pluck thee from thy dewy bed!'