Percy Bysshe Shelley’s elegiac poem “Adonais” was written to mourn the death of which other poet?

“Adonais” is an elegiac, 55 stanza poem written in the spring of 1821 when Percy Bysshe Shelley (4 August 1792 – 8 July 1822) heard of Keats' death (seven weeks earlier). It is subtitled “An Elegy on the Death of John Keats”.

Keats died at the early age of 25 because, like his poet-hero Thomas Chatterton, he had poisoned himself through self-medication for some unspecified ailment (thought to have been venereal disease). Despite being a trained physician, Keats had turned to the ingestion of mercury as a cure and by August 1818 Keats was poisoned in body and mind – like the “pale warriors” of “La Belle Dame sans Merci”, loitering disconsolately between life and death. In this very vulnerable and weak state he undertook to spend three stressful months caring for his dying younger brother, Tom, in the process contracting the tuberculosis that set him on the road to an early grave.

John Keats, young poet of “Ode to a Nightingale”, “To Autumn”, "The Eve of St. Agnes", "La Belle Dame sans Merci", "Hyperion", "Lamia" and many other works, died in Rome on February 23 1821. He had travelled to Italy to find a cure for the “family disease” and to take up an invitation from the Shelleys to stay with them, to convalesce, at their home in Pisa.

A little more than a year later, on 8 July 1822, less than a month before his thirtieth birthday, Shelley himself died, drowned as a result of the sinking of his sailing boat in a sudden storm on the Gulf of Spezia.