Herschel L. Carnahan (August 31, 1879 – March 31, 1941) was the 30th Lieutenant Governor of California, 1928–1931, serving under Governor C. C. Young. He was a Republican. Born and raised in Illinois, Carnahan came to California in May 1896 at age 18, seeking treatment for tuberculosis, living at first with an uncle on a ranch at Alessandro, in Riverside County. Carnahan took work as an elementary school teacher later that year, and went on to work as a both a teacher and a school principal in Winchester. He was also active in the temperance movement.