True, but I think it probably happened much faster and before Wilson - who may be the worst president of the 20th century. The Black Codes were enacted right after the war and the 14th Amendment did little in many states to prevent the submission of freed slaves (and as a result poor whites) to the same class of wealthy planters who ruled before the war. Jim Crow south was strongly in place soon after the war in the 1870's long before Wilson took office - even though as a historian he was busily rewriting history and crucial to forming the myth of the Lost Cause of the Confederacy.
The north certainly tried to prevent the South from infringing African American freedom, but it is clear that the norther economy had its own interests supporting wealthy Southerners. Obviously, the laws that the South would put into place to control their recently freed blacks were modeled on the laws that the Northern states had in place before the civil war to segregate their own free black populations and prevent them from voting.
In the end, freed blacks really did not have a chance to prosper in the South primarily because their only allies against the political will of White Supremacist Southerners were White Supremacist Northerners.