I know I keep going back to France, but then, it is a country with such a variety of stamp issues, it's a sheer delight! Their definitives are great, and so are their commemoratives. The tourism sets are beautiful, as are the arts sets and the various heraldic stamps. Rich pickings for any thematic collector!
I won a number of French stamps at a raffle the other day, and they turned out to be all part of a number of sets called the History of France, issued from 1966 onwards. Their proper name, by the way, is "Grands noms de l'Histoire". Sounds better, doesn't it?!
So they've now become my latest object of study. I'm trying to get all the sets together (there are eight sets in total) and will then piece together the history of France!