Depression cakes
I think I read somewhere that carrot cake was one of the cakes developed during the Depression era and also during WWII, (in old cookbooks you'll see 'Victory Cakes'), when supplies like butter and eggs were in short supply. Crafty bakers came up with using oil as a substitute and voila! a tradition was born. I have a recipe for a vegan chocolate cake that came from WWII, that uses no eggs, or dairy and it's pretty darn good!