The deaths of his father (in 1598) and of his elder brother, Sir Henry Beaumont (in 1605), made the poet the head of this brilliant family: the dramatist, Francis Beaumont, was his younger brother. John went to Oxford in February 1597, and entered as a gentleman commoner in Broadgate's Hall, later Pembroke College. He was admitted to the Inner Temple in 1600, but when his brother Henry died he is thought to have returned to Grace-Dieu to manage the family estates.
He began to write verse early, and in 1602, at the age of nineteen, he published anonymously his Metamorphosis of Tobacco, written in very smooth couplets, in which he addressed Michael Drayton as his loving friend. He lived in Leicestershire for many years as a bachelor, before eventually marrying a member of the Fortescue family. They had four sons, the eldest of whom, another John, was considered one of the most athletic men of his time. The younger John Beaumont edited his father's posthumous poems, and wrote an enthusiastic elegy on him, but was killed in 1644 at the Siege of Gloucester. Another of Beaumont's sons, Gervaise, died in childhood, and the circumstances of his death are recorded in one of his father's most touching poems. Beaumont's major work is a poem in twelve books, entitled The Crow of Thornes, which was greatly admired in manuscript by the Earl of Southampton and others. Though lost for centuries, scholars have established that a long poem in twelve books contained in a British Library manuscript was indeed Beaumont's lost major work.
After long retirement, Beaumont was persuaded by the Duke of Buckingham to return to society; he attended court and in 1626 was made a baronet. Shortly afterwards, he died, and was buried in Westminster Abbey. His son, John, succeeded him as baronet.
The new Sir John, the strong man, published in 1629 a volume entitled Bosworth Field; with a taste of the variety of other Poems left by Sir John Beaumont. No more tastes were ever vouchsafed, so Beaumont's reputation rests on this the juvenile Metamorphosis of Tobacco. Beaumont's favoured medium was the heroic couplet. Bosworth Field, the scene of the battle described in Beaumont's principal poem, lay close to the poet's house of Grace-Dieu. He always wrote with a remarkable smoothness, which marks him, with Edmund Waller and George Sandys, as one of the pioneers of the classic reformation of English verse.
The poems of Sir John Beaumont were included in Alexander Chalmers's English Poets, vol. vi (1810). An edition, with memorial introduction and notes, was included (1869) in Dr AB Grosart's Fuller Worthies Library; and the Metamorphosis of Tobacco was included in JP Collier's Illustrations of Early English Popular Literature, vol. i. (1863).