The historical background
The ideals of the Whig party, at least of the radical wing of the party, were those of Percy Bysshe Shelley himself: religious toleration, abolition of the slave trade, reform of rotten boroughs. Shelley thus grew up in an age which seemed to him dominated by the forces of repression. The Mask, written on the occasion of Peterloo in 1819, is probably Shelley’s most famous political poem, and the occasion of its composition is indicative of the state of the country at that time. Shelley shows himself a master of pictorial effect in his portrayal of the bloody army of Church and State – and the word ‘blood’ sounds through the poem like a drumbeat – in its triumphant progress with sword and cavalry. The state of Shelley’s England did not please him, but the state of Ireland was much worse.