Henry Koster (1793–1820): Son of the Lisbon merchant, John Theodore Koster. At the age of only sixteen his father sent him to Brazil, both for his health and to set up as a sugar planter. Koster travelled extensively in Pernambuco and returned to England only briefly in 1811 and again in 1815. On the latter occasion, his visit to Southey in Keswick turned into a prolonged stay after Koster was injured in a coach accident.

William Knox (1789–1825): Born in Roxburghshire, Knox was the son of a farmer. He attended Musselburgh grammar school and between 1812–1817 farmed at Wrae, near Langholm, Dumfriesshire. He returned to live with his parents after his farm failed. The family settled in Edinburgh in 1820 and Knox became a writer, supported by John Wilson, who often gave him money. Knox contributed to the Literary Gazette and other journals and published three collections of his own poetry: The Lonely Hearth (1818); The Songs of Israel (1824); and The Harp of Zion (1825).

Herbert Knowles (1798–1817): A member of a family of Nonconformist cloth merchants and manufacturers from Gomersal, near Leeds, Herbert was orphaned in 1805. His relatives eventually recognized his academic talents and he was sent to Richmond Grammar School. Knowles was concerned that he did not have the funds to enter Cambridge University (and possibly that his family would not be prepared to support his ambition to study there).

William Knighton (1776–1836): Courtier and physician. He became a friend of Henry Herbert Southey while the two men were studying medicine at the University of Edinburgh, and set up a London practice in 1806. He was appointed physician to the Prince of Wales (the future George IV) in 1810 and gradually assumed the role of sorting out the Prince’s tangled finances. In 1822 he became Keeper of the Privy Purse and, effectively, George IV’s private secretary. Knighton furthered Henry Herbert’s career, ensuring he succeeded him as physician to George IV in 1823.

John King [Nicholas Johann Koenig] (1766–1846): Bristol-based surgeon, painter and linguist, originally from Berne, Switzerland. He came to England in the 1790s and studied medicine under John Abernethy (1764–1831; DNB) at St Bartholomew’s Hospital, before settling at Clifton in Bristol. He married Emmeline Edgeworth, a sister of the novelist Maria (1768–1849; DNB). Southey came to know King well when he succeeded Davy in his role at the Pneumatic Institution in 1801.

Emmeline King (1770–1847): Younger sister of Maria Edgeworth (1768–1849; DNB). She married John King in 1802 and the couple had two daughters.

John Kidd (1775–1851): Doctor and author of medical treatises. Educated at Westminster School and Christ Church, Oxford (matric. 1793, BA 1797). A friend of Southey’s during his time at Oxford, and possibly a school friend as well.

John Kenyon (1784–1856): Kenyon was a very wealthy man. On the death of his father, John Kennion (d. c. 1792), he inherited a share in the sugar-producing estate of Chester in Trelawny, Jamaica, and the two hundred enslaved persons who worked the estate. Though he was born in the West Indies he left as a child and was educated at Charterhouse and Peterhouse, Cambridge. He lived mostly in the West Country and then London, though he also travelled a great deal. Kenyon’s first wife, Susannah Wright, died in Naples in 1818 and he married Caroline Curties (d. 1835) in 1821.

Thomas W. Kelly (b. c. 1800): Poet, born in London of Irish parentage. His works included Myrtle Leaves; A Collection of Poems, Chiefly Amatory (1824). He briefly corresponded with Southey in 1827 after he found one of the latter’s manuscript letters to a friend, now deceased, in a book he had purchased. He offered to return it, but Southey told him to keep the letter, on the condition that it was not published during his lifetime.

Montague Henry Kelly (1773–1838): Son of Captain Redmond Kelly (d. 1798), an Irish soldier who lived in Dean’s Yard, Westminster in later life and sent his three sons to Westminster School. Montague Henry Kelly attended Westminster School from 1786 to 1791, where he was a friend of Southey’s. Kelly pursued a Naval career from 1791 onwards, reaching the rank of Commander in 1830, but was often in debt – he spent the years 1806–1809 in the Fleet prison. In 1801 he eloped with the sixteen–year old Eliza Smith (1785–1857), daughter of the painter, John Raphael Smith (1751–1812; DNB).