Also, you have countries that do not exist anymore; Norwegian author Bjørn Berge published a book (Since translated into English with the title 'Nowherelands')

Also, you have countries that do not exist anymore; Norwegian author Bjørn Berge published a book (Since translated into English with the title 'Nowherelands') in which he briefly sketches the circumstances that brought countries like Tripolitania, Heligoland and Batum into - and out of - existence, accompanied by a selection of stamps from said countries. It made for quite interesting reading for me, who've always been a geography geek.