Born in Santa Rosa, New Mexico, Campos received a Juris Doctor from the University of New Mexico School of Law in 1953.

He was a seaman in the United States Navy during World War II, from 1944 to 1946.

[2] On June 2, 1978, Campos was nominated by President Jimmy Carter to a seat on the United States District Court for the District of New Mexico vacated by Judge Harry Vearle Payne.

He served as Chief Judge from 1987 to 1989, assuming senior status on December 26, 1992, and serving in that capacity until his death of cancer, in Santa Fe.

The Santiago E. Campos United States Courthouse was renamed in his honor in 2004.