James Cook Conkling (October 13, 1816 – March 1, 1899) was an American politician and attorney from New York City. A graduate of Princeton College, Conkling was admitted to the bar, then moved to Springfield, Illinois. There, he became a prominent Whig, serving first as mayor and later in the Illinois House of Representatives. In 1856, he became one of the first Republicans in the state, attending the Bloomington Convention with Abraham Lincoln. Twice a presidential elector, Conkling was a State Agent during the Civil War and returned to the Illinois House in 1866. Later in his life he was a postmaster and a trustee of the University of Illinois.