This would best be called The Stamps and Postal History of the Principality of Zlobenia and the Grand Duchy of Borogravia, and the Consequences of the Ongoing War between the two states - but it is a bit too long to fit anywhere.
Discworld fans will be mostly familiar with Borogravia (and neighbouring Zlobenia) from the events described in The Monstrous Regiment*. The two countries squabble and go to war in a never-ending boundary dispute over the ever-changing course of the Kneck River. And as any philatelist will tell you, war provides some interesting by-products in terms of stamp, postal history, and Cinderellas. This little war is no different. Discworld Stamp Collectors had a single Zlobenian stamp for their albums way back in the Year of the Signifying Frog. It wasn’t until the Year of the Spinning Mouse that the second true Zlobenian and first Borogravian stamps came along. But there is enough material from in-between for a small collection based on this region of Discworld. As yet, no stamps from Mouldavia. the other state in the region, have appeared.
To kick things off, the Troll Bridge of Tubz is situated in Borogravia, and this featured in one of the Wonders of Discworld miniature sheets from the Year of the Reciprocating Llama. The six stamps show the troll on the lookout while a goat not only slips past behind him, but also photo-bombs the troll in the last of the sequence.