Educated at Syon House Academy (1802-04), Eton (1804-10) where he was nicknamed "Mad Shelley" and University College, Oxford (1810-11), Shelley developed a strong hatred of bullying and tyranny. Expelled from Oxford in 1811 with his friend Thomas Jefferson Hogg for writing The Necessity Of Atheism, a pamphlet attacking aspects of Christianity, Shelley eloped with his 16 year old bride Harriet Westbrook by whom he would later have two children, Ianthe and Charles. 

They travelled first to Scotland before travelling on to Dublin and then Lynmouth in Devon where he wrote The Declaration Of Rights and Queen Mab, a poem celebrating the merits of republicanism, atheism, vegetarianism and free love. Departing for Wales they eventually returned to London where Shelley met with fellow radicals Leigh Hunt and William Godwin, whose daughter Mary he fell in love with and eloped to France in the summer of 1814.

With the death of his grandfather the will provided Shelley with an annual allowance with which to pay his debts. Settling in Windsor in 1815 Shelley renewed his friendship with Thomas Jefferson Hogg and associated with Thomas Love Peacock. Here he wrote Alastor-The Spirit of Solitude that warns of abandoning love in pursuit of a dream.

In the spring of 1816 Shelley and Mary with Claire Clairmont, her stepsister, journeyed to Geneva to rendezvous with Lord Byron, with whom Claire had begun an affair. Mary commenced work on her gothic novel Frankenstein, while Shelley composed the poems Mont Blanc and Hymn to Intellectual Beauty.

Back in England Mary had a son, William, by Shelley and with his wife Harriet committing suicide this allowed them to marry in December of that year, however the courts declared him unfit to raise his children, Ianthe and Charles, who were placed in foster care. In 1817 the Shelleys were now living at Marlow. Here Mary finished Frankenstein and Shelley wrote The Revolt of Islam that tells of revolution and their daughter, Clara, was born.

With his health suffering and living beyond his means they decided in 1818 together with Claire to go to Italy to meet up again with Byron. Away from British politics at Bagni di Lucca Shelley was more freely able to express his visions and ideals in such poems as Ode to the West Wind, Ode to Liberty, The Cloud and To a Skylark.

They travelled to Venice to see Byron and stayed the summer. Their daughter Clara became ill and died and Shelley wrote Lines Written Among the Euganean Hills and Julian and Maddalo. They departed for Naples for the winter settling in Rome in the spring of 1819 where Shelley wrote Prometheus Unbound and The Cenci. With the death of their son William from malaria they fled north to Livorno, then to Florence where their only surviving child Percy Florence Shelley was born.

Outraged at the Peterloo Massacre Shelley wrote The Mask of Anarchy in protest and later Peter Bell the Third, an attack on corrupt British society.

Moving to Pisa in 1820 he wrote Oedipus Tyrannus about adultery and Epipsychidion that mythologizes an infatuation with a young admirer. He wrote Adonais on the death of Keats and Hellas celebrating the Greek revolution for human liberty, and in 1821 Byron arrived to renew their friendship.

1822 saw Shelley settle near Lerici where he lived until he sailed across the Gulf of Spezia with Edward Williams to welcome his old friend Leigh Hunt. Shelley and Williams drowned on 8th July 1822 when their boat sank at sea in a storm. Shelley's body was washed ashore several days later, it was cremated in a funeral pyre on the shore of Via Reggio surrounded by three of his closest friends Edward Trelawny, Leigh Hunt and Lord Byron. His heart refused to burn, Trewlany snatched it from the pyre and gave it to Mary Shelley who kept if for the rest of her life. 

Shelley's ashes were stored for several months in the British Consul's wine cellar in Rome before eventually being buried in the Protestant Cemetery there. When Mary Shelley died in 1851 her husband's heart was found amongst her belongings, it was apparently wrapped in one of the sheets of  Adonais - Shelley's famous elegy to Keats. His heart now lies in St Peter's Churchyard, Bournemouth, England, near to the former Shelley family country home at Boscombe Manor. Mary Shelley's body is buried there as well and the remains of Mary's parents, William Godwin and Mary Wollstonecraft, were brought over from Old St. Pancras Churchyard, London and rest in the same grave. There is a monument to Percy Bysshe Shelley in nearby Christchurch Priory.

Keats~Shelley Memorial Association