Waddington's, 1971, 2-7 players, no age range specified so let's go with 12 and up. I picked this game up from eBay based on its venerable status as a classic. Unfortunately, nobody in my group seems too keen on trying it out. Admittedly, it does look a little dry, at least by our standards. It feels like it should be a war game, but there's no bloodshed. Also, the lack of any kind of random element (which, love it or hate it, does introduce a little bit of excitement into any game), makes it seem like some kind of game you might pull out in school to (gasp) learn something. Anyway, rather than allow it to gather any more dust in my basement, back to eBay it goes.
This game has been in print for decades, most notably by Avalon Hill.