James Terrance Mullen (August 30, 1843 – July 6, 1891) was the first Supreme Knight of the Knights of Columbus from February 2, 1882 to May 17, 1886. He also served in the New Haven, Connecticut police and Fire Departments, and as an alderman. With his service in the Union Army and in several fraternal orders, he has been described as "veteran of fraternity."
Mullen was born in New Haven, Connecticut, U.S. on August 30, 1843, and attended the public schools there. He married Anne Elizabeth Pigott, the sister of Congressman James P. Pigott. They had one son. His nephew, William P. Cronan, served as the 19th Naval Governor of Guam.