The year 1827 (MDCCCXXVII) was a common year starting on Monday (link will display the full calendar) of the Gregorian Calendar and a common year starting on Saturday of the 12-day slower Julian calendar.

William Blake (28 November 1757 – 12 August 1827) was an English poet, painter, and printmaker. Largely unrecognised during his lifetime, Blake is now considered a seminal figure in the history of both the poetry and visual arts of the Romantic Age. His prophetic poetry has been said to form "what is in proportion to its merits the least read body of poetry in the English language". His visual artistry has led one contemporary art critic to proclaim him "far and away the greatest artist Britain has ever produced". Although he lived in London his entire life except for three years spent in Felpham he produced a diverse and symbolically rich corpus, which embraced the imagination as "the body of God", or "Human existence itself".

Considered mad by contemporaries for his idiosyncratic views, Blake is held in high regard by later critics for his expressiveness and creativity, and for the philosophical and mystical undercurrents within his work. His paintings and poetry have been characterised as part of both the Romantic movement and "Pre-Romantic", for its large appearance in the 18th century. Reverent of the Bible but hostile to the Church of England – indeed, to all forms of organised religion – Blake was influenced by the ideals and ambitions of the French and American revolutions, as well as by such thinkers as Jakob Böhme and Emanuel Swedenborg. Despite these known influences, the singularity of Blake's work makes him difficult to classify. The 19th-century scholar William Rossetti characterised Blake as a "glorious luminary," and as "a man not forestalled by predecessors, nor to be classed with contemporaries, nor to be replaced by known or readily surmisable successors".