Percy Bysshe Shelley is one of the leading and most prolific of the English Romantic poets of the early nineteenth century. His contributions to English literature are substantial, beginning with his classic lyric poems and continuing through philosophies regarding nonviolent protest that are said to have influenced Marx, Tolstoy, Thoreau, and King.
As a Romantic poet, Shelley's best known works include "Ozymandias," a meditation on the transience of life even of history's most renowned men and women, and "Ode to the West Wind," a meditation on the relationship between Nature and the work of the artist. "Hymn to Intellectual Beauty" is the poet's conception of the relationship of beauty, truth, love, and spirituality and is in some ways a lyrical manifesto of how Romantics sought to understand and revel in man's existence—themes that would be carried further by the subsequent Victorians and Pre-Raphaelites.
Shelley's progressivism was considered radical during his lifetime; consequently, he sometimes had difficulty getting work published. He did not withhold his opinions as a social and economic reformer and his political writing was considered divisive but nonetheless influential for generations afterward, even outside the literary world.
I think that Shelley does occupy an important role in English Literature primarily because of his own unique take on Romanticism. Shelley is able to bring out the fundamental concerns that the artist might hold towards their own work and their own creative state of being in the world. One of Shelley's fundamental concerns would be how the artist can be remembered after they pass. In this, Shelley is one of the first thinkers to bring out the idea that the artist actually suffers two deaths. The death that everyone else experiences, and the death of their art. The death of the artist's name or their work might be even more painful to endure because it represents glory and prestige that once was. Recall this idea with his poem "Ozymandias," in which the decrepit statue, in the middle of the desert, no longer the tower of inspirational strength it once was reads, "King of Kings." This is a metaphor that Shelley feels that applies to all artists. Shelley spent much of his poetry wondering how he can achieve artistic immortality because he understood it impossible to gain physical immortality. At the same time, Shelley's examination of the transcendent nature of art and artist is what makes his contribution to English Literature so profound and significant.