John Evelyn (31 October1620 - 27 February 1706) was an English writer, gardener and diarist.

Evelyn's diaries are largely contemporaneous with those of the other noted diarist of the time, Samuel Pepys, and cast considerable light on the art, culture and politics of the time (he witnessed the deaths of Charles I and Oliver Cromwell, the last Great Plague in London, and the Great Fire of London in 1666.). Evelyn and Pepys corresponded frequently and much of this correspondence has been preserved.

Born into a family whose wealth was largely founded on gunpowder production, John Evelyn was born in Wotton, Surrey, and grew up in the Sussex town of Lewes. He was educated at Balliol College, Oxford and at the Middle Temple. While in London, he witnessed important events such as the execution of Thomas Wentworth, Earl of Strafford. Having briefly joined the Royalist army, he went abroad to avoid further involvement in the English Civil War and married Mary Browne, daughter of the British ambassador in Paris.

In 1652, Evelyn and his wife settled in Deptford, in south-east London. Their house, Sayes Court (adjacent to the naval dockyard), was purchased by Evelyn from his father-in-law Sir Richard Browne in 1653 and Evelyn soon began to transform the gardens. In 1671, he encountered master wood-worker Grinling Gibbons (who was renting a cottage on the Sayes Court estate) and introduced him to Sir Christopher Wren.

It was after the Restoration that Evelyn's career really took off. His treatise Sylva, or Discourse on Foreign Trees (1664) was written as an encouragement to landowners to plant trees to provide timber for England's burgeoning navy. He was a member of the Royal Society and, as a leading churchman, was closely involved in the reconstruction of St Paul's Cathedral by Wren (with Gibbons' artistry a notable addition).

In 1694 Evelyn moved to Wotton in Surrey and Sayes Court was made available for rent. Its most notable tenant was Russian tsar Peter the Great who lived there for three months in 1698 (and did great damage to both house and grounds). The house no longer exists, but a rundown public park of the same name can be found in Evelyn Street.