Take a look at this thread - someone else had the same error as you, same situation. It turns out that there was an issue with running the actual insert, which resulted in no record being inserted. Then when SCOPE_IDENTITY() was called, it returned null, since no record was inserted.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.