Asymptotic Freedom and the Emergence of QCD
  I describe our understanding of the strong interactions at the end of the 1960's and the impact of the experiments on deep inelastic scattering. I recall the steps that lead from the attempts to understand these experiments to the discovery of asymptotic freedom in 1973 and the subsequent rapid emergence, development and acceptance of the non-Abelian gauge theory of color (QCD) as the theory of the strong interactions. 
David J. Gross