The German chocolate,Pineapple upside down and bundt cakes were popular in the 70.s Red food die was banned at that time so we didn't see red velvet cake for awhile.
Black Forest Torte.

I think here in the US the black forest didn't really get popular until the 80s? I live so far out west I had not heard of one until then anyway.
But if what you mean by style is a theme cake then what about
a Watergate cake with cover up frosting?
http://www.mom-mom.com/watergate_cake.htm
oh and there were dump cakes. YUK