Erskine Caldwell the precursor of John Steinbeck? Contemporaries would be more correct I think. They were born about a year apart (Steinbeck, the older), and had published about the same time the early works that set their fame.
The years have been much kinder to Steinbeck than Caldwell, I believe. His works often appear in new editions--I think Penguin published many for the centennial of his birth--while Caldwell has been basically overlooked.
The film of GLA was a hoot!