William Knox was born in Firth, in the parish of Lilliesleaf, Roxburghshire, on 17 August 1789, the first son of the farmer Thomas Knox and his wife Barbara Turnbull. His education was carried out at the local parish school and Musselburgh grammar school, and in 1812 he took on the lease of a farm near Langholm. Farming was obviously not for him, as he gave it up after only five years, turning instead to his real love – writing poetry. He had composed verses from an early age and contributed frequently to magazines; by 1818 his first collection The Lonely Hearth and other poems was published, followed six years later by The Songs of Israel: consisting of lyrics, founded upon the history and poetry of the Hebrew Scriptures, in 1824, and The Harp of Zion: a series of lyrics, founded upon the Hebrew Scriptures in 1825. The two latter volumes were published in Edinburgh.
Luckily for one attempting to make a living from writing, his work was well received, attracting the attention of Sir Walter Scott, who, according to James Grant Wilson in The Poets and Poetry of Scotland, Vol. II, (Blackie, 1877) 'afforded him kindly countenance and occasional pecuniary assistance.' Knox also wrote some prose works, but it was his poetry which appealed to the reading public, and continued to do so for some time after his death – a collected edition was published in London in 1847. Scott wrote: ‘His talent … showed itself in a fine strain of pensive poetry’. As the subtitles of his books attest, his poems were full of religious sentiment, in some cases paraphrases of scriptural texts; they were the moralising, uplifting poems of the sort that was popular during the Victorian era, and President Lincoln's appreciation of Knox's poem 'Mortality' is well-documented.
Modern Scottish Poets [Vol.15] (Brechin,1893) records that 'Knox fell a victim to the undue gratification of his social propensities'; he had squandered health and wealth both, and died of a paralysis in Edinburgh on 12 November 1825, aged only 36. He is buried in Old Calton Burial Ground, not far from the American Civil War Memorial, which incorporates a statue of Lincoln.