The first one that I finished this last week was Osprey Warrior #173: Mamluk 'Askari 1250 – 1517. I had heard a bit about them, but mostly later in their history, when they faced Napoleon, so this, their origin story filled in a bit of information for me.
Next was My Storytelling Guide Companion, another RPG gaming item, which was somewhat less useful than another book by the same author. Not great, not bad, not special.
Then, In Holy Terror: Reporting the Ulster Troubles by Simon Winchester. The author had been reporting on Ulster during the early days of the disturbances there, and was actually present at Bloody Sunday. This makes the book quite interesting for someone who recalls the garbled reports of our Press at the time. The book is hard to find, but if you have any interest in Irish/British relations, it might be worthwhile to read.
Finally, Osprey Elite #33: South-East Asian Special Forces. Not only South Vietnam is covered, though that pretty thoroughly, but also places like Indonesia and Thailand. Mildly engaging.