Between 1919 and 1933 Columbia was the focal point of the ferment that marked the next stage in the history of the realist movement. Although new ideas were being aired in other law schools there was a greater concentration of energetic and radical jurists at Columbia than anywhere else; furthermore the implications of some of the new ideas that were being bandied about were given focus by becoming the subject of sharp controversy both within and outside the law school. A series of spectacular events, notably the curriculum discussions of 1926–8, the deanship crisis of 1928, and Llewellyn's debate with Pound in 1931, dramatized the jurisprudential issues and helped to make them a matter of public concern among academic and practising lawyers. It was during this period that the existence of a new movement began to be recognized and that, almost at the same time as it became visible, the movement split in two.

The story can be said to begin with the appointment of Walter Wheeler Cook to the Columbia faculty in 1919. At the time Columbia Law School was considered by many to be second only to Harvard in prestige. It was larger than the Yale Law School and had a longer and more distinguished tradition. The famous legal scholar James Kent had been Professor of Law at Columbia from 1793 to 1797 and from 1823 to 1846.