In 1841, Clare escaped. He walked home to Northamptonshire along the Great York Road, a distance of some 90 miles. He was so hungry that he ate the grass by the roadside. At night he lay down with his head pointed towards the north so that he would know which way to go in the morning. On returning home, he recorded his journey in a piece of prose writing of astonishing honesty and clarity. But shortly afterwards he was again removed, this time to the Northamptonshire General Lunatic Asylum (later known as St Andrew's Hospital, it would be the place where James Joyce's daughter Lucia found herself confined).

Clare lived and wrote in the Northampton asylum for more than 20 years, until his death in the summer of 1864. His voice dried up and dementia set in towards the end, but it was in the asylum that he wrote some of his most haunting, visionary lyrical poems:

I am — yet what I am, none cares or knows;
My friends forsake me like a memory lost:
I am the self-consumer of my woes —
They rise and vanish in oblivion's host,
Like shadows in love-frenzied stifled throes —
And yet I am and live — like vapours tossed

Into the nothingness of scorn and noise,
Into the living sea of waking dreams
Where there is neither sense of life or joys
But the vast shipwreck of my life's esteems;
Even the dearest that I loved the best
Are strange — nay, rather, stranger than the rest.

I long for scenes where man hath never trod,
A place where woman never smiled or wept,
There to abide with my Creator, God,
And sleep as I in childhood sweetly slept,
Untroubling and untroubled where I lie,
The grass below — above, the vaulted sky.

Clare has always been a poet's poet. Important selections of his verse were edited by the 20th-century rural poets Edmund Blunden and Geoffrey Grigson. More recent poets from Ted Hughes and Seamus Heaney to Tom Paulin, Kathleen Jamie and Glyn Maxwell have been huge admirers. But he has never been an academic's poet. His words seem almost too pellucid for the taste of critics reared on T. S. Eliot's code of poetic difficulty. And yet his technical range is astonishing: there are hundreds of sonnets, many in highly innovative variations upon the usual rhyme schemes of the form; there are long and lively narrative poems, songs and ballads, extended descriptive pieces, philosophical reflections. There is poem after poem on birds and birds' nests, flowers and fishponds, ploughed fields and little acts of trespass.