Q:

What does "thou art come unto a feast of death" mean?

I came upon this sentence while reading the narrow road to the deep north. I knew it's from Shakespeare but can't understand. 

Thou art come unto a feast of death

A:

It means "You have come to a feast of death."
In earlier forms of English, we used the auxiliary verb be with some verbs, including come. The word art is the second-person singular form of be.

