Is that leather?
 

https://en.wikipedia.org/wiki/Artificial_leather.

I've read that Ford used "leatherette" for their V8 rumble seats for weather durability, as opposed to leather which was continuously problematic throughout the car's years of use.

Re: Is that leather?
 

Leatherette was used on seat side and back panels on those cars having leather seats, as well as on rumbleseats, and were not restricted to V8s. Door panels were a matching cardboard. I’m not aware of any official explanations given by Ford on any subject.

Re: Is that leather?
 

The name of the material that Ford used for those purposes was, in Ford terminology, pyroxylin cloth which is still in use today on the covers of some hard bound books. In fact, when Roy Nacewicz (RIP) offered reproductions of the '32-'34 and '37 versions, he sourced it to a company serving the book binding trade. Lucky were those restorers who obtained it from Roy while it was offered as it was (and remains) a perfect match for the original material used in those applications.

Re: Is that leather?
 

As David mentions, the pyroxylin or lacquer coated cloth was a standard of the industry at the time. Vinyl upholstery fabric wasn't really in the picture much until after the war. Vinyls are thicker and heavier so it can sometimes not be a very good replacement for the early type leatherette materials where the thickness and grain pattern differences are obvious. A lot depends on how original a person wants to get on a restoration.