Professor Ferrell is a student of American foreign policy and generally of American history. He came to Indiana University in 1953 and became a full professor in 1961. He has taught at many institutions, the last being the United States Military Academy.

He has published many books, including Woodrow Wilson and World War I and, most recently, America's Deadliest Battle: Meuse-Argonnne, 1918 (University Press of Kansas, 2007).