Nicholas Blake is the pseudonym of poet and author, Cecil Day-Lewis, used primarily for his mystery series. Cecil Day-Lewis CBE (1904 - 22) was a British poet from Ireland and the Poet Laureate from 1968 until his death in 1972. He is the father of actor Daniel Day-Lewis and documentary filmmaker and television chef Tamasin Day-Lewis.

Day-Lewis was born in Ballintubbert, County Laois, Ireland. He was the son of the Reverend Frank Cecil Day-Lewis and Kathleen Squires. After Day-Lewis's mother died in 1906, he was brought up in London by his father, with the help of an aunt, spending summer holidays with relatives in Wexford. Day-Lewis continued to regard himself as Anglo-Irish for the remainder of his life, though after the declaration of the Republic of Ireland in 1948 he chose British rather than Irish citizenship, on the grounds that 1940 had taught him where his deepest roots lay. He was educated at Sherborne School and at Wadham College, Oxford, from which he graduated in 1927.