I imagine it was the cold winter, they are barely hardy. Are you sure its dead(?), try scraping a bit of the bark or perhaps give it a few more weeks. My solanum (I have the more tender white flowering one) has just made it through, some new buds and leaves on it now, but a neighbouring one (elsewhere on my road) seems like it may not.

They do need a sheltered west or south-west facing position, Bryant. I agree with Weatherwise - my Solanum laxum is struggling a bit, but it is alive. I had to prune out quite a bit of dead wood from my S. crispum.