Remember that scene of America searching up things in 1942? Which obviously was impossible… Why and How? Explanation or theory behind it all?

I think it’s just a silly comic gag. There isn’t much of an explanation.

You’ll see that at times, Hima likes to include anachronisms for the sake of humour. He’s fully aware of what he’s doing and makes sure the characters do too. 

The anachronisms in the Roman era are the funniest to me.