Board Thread:Questions and Answers/@comment-2.122.199.184-20141111223147/@comment-4411406-20150505154116

Ever since HYDRA was first introduced, the symbol has always been a skull with six tentacles. I don't think it was ever explained why they went with this design but I guess it could be that the skull can stand for death and destruction and the tentacles can stand for they way the organization can reach into the murky depths of the criminal world.

I know that's how the octopus symbol for S.P.C.T.R.E. from the James Bond films was explained. And it possible they based the HYDRA Logo off of the S.P.E.C.T.R.E. logo since James Bond was kind of an influence for Nick Fury and S.H.I.E.L.D. Of course it can all be easily explained as since they made Red Skull the leader of HYDRA, the skull stands for him.

I did add information about the creation of the HYDRA logo for the film on the HYDRA page in the Behind the Scenes Section if that helps any.