Ludwig Sherman Gerlough was born in Cheyenne, Wyoming, on January 16, 1887, the eldest of six children born to a miner and housewife. The Gerlough family relocated to Boise, where Ludwig Gerlough graduated from high school in 1905.

Gerlough completed his bachelor's degree at the University of Idaho in 1909, and then taught math and history, and coached football at Moscow High School from 1909 to 1911. After proposing marriage to fellow teacher Margaret Lauder in 1911, Gerlough matriculated at Oxford University, England, as one of the first Rhodes Scholars from the state of Idaho.

After Gerlough earned his second bachelor's degree at Oxford in 1914, he returned to the U.S. and married Margaret Lauder. The nuptials took place in San Diego, where the groom had secured a teaching position at San Diego High School. The couple had two children, Daniel Lauder Gerlough (1916-1977), a professor of Transportation Engineering, and Eleanor Gerlough Elmendorf (1920-), a science librarian.

Ludwig Gerlough received his master's degree from Oxford in 1918. He taught at San Diego High School and Lowell High School, a college preparatory school in San Francisco, until his retirement.

He participated in the Y.M.C.A., the Beta Theta Phi fraternity, and the American Historical Association. Gerlough enjoyed traveling, theater, and sports. Upon his wife's death, he moved to Minneapolis to live with his son Daniel, who preceded him in death. Ludwig Gerlough died on March 15, 1978.