Cornelius Mathews was an American writer, best known for his crucial role in the formation of a literary group known as Young America in the late 1830s, with editor Evert Duyckinck and author William Gilmore Simms.

Cornelius Walford (1827–1885), was an English writer on insurance.

Cory Efram Doctorow is a Canadian-British blogger, journalist, and science fiction author who served as co-editor of the blog Boing Boing. He is an activist in favour of liberalising copyright laws and a proponent of the Creative Commons organization, using some of their licences for his books. Some common themes of his work include digital rights management, file sharing, and post-scarcity economics.

Cosmo Hamilton, born Henry Charles Hamilton Gibbs, was an English playwright and novelist. He was the brother of writers Arthur Hamilton Gibbs, Francis William Hamilton Gibbs, Helen Katherine Hamilton Gibbs and Sir Philip Gibbs.

John Coulson Kernahan was an English novelist.

Countee Cullen was an American poet, novelist, children's writer, and playwright, particularly well known during the Harlem Renaissance.

Courtney Ryley Cooper was an American circus performer, publicist and writer. During his career he published over 30 books, many focusing on crime; J. Edgar Hoover considered him at one time "the best informed man on crime in the U. S." He was also an expert on circuses, and was the chief publicist for Ringling Brothers, Barnum & Bailey Circus at the time of his death.

Coventry Kersey Dighton Patmore was an English poet and literary critic. He is best known for his book of poetry The Angel in the House, a narrative poem about the Victorian ideal of a happy marriage.

Crosbie Garstin was a poet, best-selling novelist and the eldest son of the Newlyn School painter Norman Garstin. He is said to have been "'untameable as a child", and to have "died in mysterious circumstances" after a boating accident in the Salcombe estuary. He is known for the Penhale trilogy of novels based in 18th-century Cornwall.

Cynewulf is one of twelve Old English poets known by name, and one of four whose work is known to survive today. He presumably flourished in the 9th century, with possible dates extending into the late 8th and early 10th centuries.