The Outbreak of Rebellion: The Army and Navy in The Civil War

 He was born Johann George Nicolay in Essingen, Rhenish Bavaria. In 1838, he immigrated to the United States with his father and attended school in Cincinnati. He later moved to Illinois, where he edited the Pike County Free Press at Pittsfield, and became a political power in the state. Then he became assistant to the secretary of state of Illinois. While in this position, he met Abraham Lincoln and became his devoted adherent.

In 1861, Lincoln appointed Nicolay as his private secretary, which was the first official act of his new administration. Nicolay served in this capacity until Lincoln's death in 1865. Shortly before his assassination, Lincoln appointed Nicolay to a diplomatic post in France.[3] After the death of the President, Nicolay became United States Consul at Paris, France (1865–69). For some time after his return to the United States, he edited the Chicago Republican.[4] He was Marshal of the United States Supreme Court (1872–1887). In 1881, Nicolay wrote The Outbreak of the Rebellion. 

Source http://en.wikipedia.org/wiki/John_George_Nicolay