Gibbs was born in Philadelphia to financier William Warren Gibbs and Frances Ayres (Johnson) Gibbs. He graduated from the DeLancey School in 1905 then entered Harvard College where he followed his own curriculum of science and engineering, studying plans of British battleships in his dormitory room. He left without a degree in 1910. He then attended Columbia Law School from 1911 to 1913, receiving a Bachelor of Law and Master of Arts in economics, both in 1913. At his father's request, he practiced law for the next two years.
