Isaac Newton Brown (May 27, 1817 – September 1, 1889) was a naval officer in both the United States Navy and the Confederate States Navy. Isaac N. Brown was born in Caldwell County, Kentucky, but spent part of his later youth in western Tennessee. In March 1834, shortly after his father died, he joined the United States Navy as a midshipman. He received a commission as a lieutenant in 1846 and later participated in the Mexican–American War. He married, owned property on the Mississippi Delta, and had three sons. He remained in the Navy and made several trips around the world on various ships.