I'm in your boat. I wrote a WW2 novel set exclusively in London, without a mention of America. I actually had an offer from a British agent (?!?!?!?!) but I haven't accepted it yet, for a few reasons. First, this guy is juuuuussstt getting started, and I think I might be better off on my own or with an experienced agent!
Second (and this was the clincher) what happens with marketing???? I can't afford to go to England! Even virtual marketing would be hard, because I don't know how it works in England at all. So...that was my major concern.
If, of course, you're super-familiar with the country in question (and feel you either won't need a real tour or can afford it) then go for it!