Nicolay, John George (nĭkˈəlā) [key], 1832–1901, biographer of Lincoln, b. Bavaria. In 1837 he was brought to the United States, and his family settled in Pike co., Ill. He worked on the Pittsfield, Ill., Free Press and was its editor and owner from 1854 to 1856. In 1860 he and his close friend, John Hay, became private secretaries to Abraham Lincoln and continued as such during his presidency. In 1890 Nicolay and Hay brought out their Abraham Lincoln: a History (10 vol.), which had been planned since 1861. It is the authorized biography, and though biased by hero worship and a sometimes excessive respect for conventions, it is a basic historical work for study of the period. Hay and Nicolay also edited Lincoln's complete works.
See biography by his daughter, Helen Nicolay (1949).