Denham, Sir John (1615–69), poet and architect, was born in Dublin, the only son of Sir John Denham (qv), lord chief justice of Ireland 1612–17, and his wife Eleanor, daughter of Sir Garret Moore (qv), Baron Mellifont and Viscount Drogheda. On 26 April 1631 he entered Lincoln's Inn to begin studies for the bar and later in the same year he matriculated (18 November) at Trinity College, Oxford, but there is no record of his ever completing his degree there.
In June 1634 he married his first wife, Ann Cotton, who was a member of a wealthy Gloucestershire family and had a personal fortune worth £500 a year. They had two daughters and two sons. Despite his wife's wealth, he was soon in financial difficulties. He was a habitual gambler; the vice blighted his early life, and Johnson later remarked that he ‘was very often plundered by gamesters’ (Johnson, Lives, 41). After losing several thousand pounds he wrote ‘An essay against gaming’ (later published, without his permission, in 1651), in the hope that it would mollify his father. On the death of his father (1639) he inherited the family estate at Egham and soon afterwards went on a gambling spree, again losing several thousand pounds. Since the 1630s he had been writing poetry, translating the second book of Virgil's ‘Aeneid’ into verse in 1636 (it was not published until 1656, however). In 1642 he presented his first work to the public when he published a play, ‘The Sophy’. This Turkish tragedy, based on Sir Thomas Herbert's Travels, was staged at the Blackfriars theatre, and was an immediate success.
At the outbreak of the English civil war, Denham was serving as high sheriff of Surrey and, proclaiming for the royalist cause, was appointed governor of Farnham castle. In December 1642 Farnham was attacked by Sir William Waller and soon fell into parliamentarian hands. Denham was sent as a prisoner to London but was soon released on conditional bail and went to live in Oxford. At this time he published his most famous and successful work, Cooper's Hill, a description in verse of the countryside around his home in Egham. This was the first topographical poem in English, but some of his critics claimed that he had bought it from an impoverished clergyman for £40; it was later accepted to have been his own work. He served as intermediary for the imprisoned Charles I, and in 1647 carried letters from Henrietta Maria to the king. In 1648 he was one of the party that carried the duke of York, later James II (qv), into exile on the Continent. He remained with the exiled Stuart princes and in 1650 was sent to Poland on a mission to raise funds among Scottish mercenaries and traders living in exile there.
On the restoration of Charles II (1660) he was rewarded for his loyalty with several grants of land and was appointed surveyor general of works (June 1660). In this capacity he oversaw the construction of Burlington House in Piccadilly and some buildings in the Greenwich Hospital. His critics claimed that he had no talent or qualifications to work as an architect. He later secured the services of Christopher Wren, who worked as his deputy. In 1661 he wrote a dramatic entertainment for the king and made the arrangements for the coronation ceremony, being made a knight of the Bath as a reward. He also served as MP for Old Sarum (1661–8).
Throughout this period he continued to write poetry. Later works included Cato Major (1648) and The destruction of Troy (1656). He also published single descriptive poems such as his lines on the crimes of a Chichester quaker (1659–60) and his description of the new royal buildings at Somerset House (1665). Some of his doggerel verse appeared in The Rump, while another satire, The famous battle of the catts in Ulster (1668), was also attributed to him. Although now largely forgotten, he was one of the most popular poets of his day, and editions of his work were still being published in the early nineteenth century. Johnson wrote that Denham was ‘deservedly considered as one of the fathers of English poetry’ (Lives, 42) and credited him with introducing descriptive poetry to the English language.
His last years were overshadowed by scandal. His first wife had died and he married (May 1665) Margaret, daughter of Sir William Brooke. She was young and attractive, and it soon became common knowledge that she was the mistress of the duke of York. Denham was seized with anger and lapsed into insanity or, as many later claimed, feigned insanity. In January 1667 Lady Denham died and rumours began to circulate that Denham had poisoned her. Denham gave his wife a lavish funeral in the hope of scotching these rumours but, faced with the anger of the London public, became a recluse in his own home. By this time he had recovered his sanity, a fact commented on (1667) in Samuel Butler's satire Hudibras. Despite his protestations of innocence, doubts about his conduct continued to be expressed until his death. The mysterious death of Lady Denham became a motif in the later writings of Marvell. Sir John Denham died in March 1669, and on 23 March was buried at Poets’ Corner in Westminster abbey, quite near the grave of Chaucer. Shortly before his death he arranged for Christopher Wren to be appointed as his successor in the surveyorship.