Does anyone have any recommendations for non-fiction history war books (WWI, WWII, Korea, Vietnam) that are appropriate for an 8yo?  I don't think he needs to know all the detailed atrocity just yet, but he really wants to study these wars, esp. Vietnam.

Try the Usborne books - especially the internet-linked ones.  The DK and Kingfisher ones are also very good.

Roald Dahl has a couple of autobiographies that my kids recently read... Boy and Going Solo. Going Solo is on the historical side, mostly about his experiences as a WW2 pilot...

They really seemed to like them... started out as a reading assignment for my still-in-public-schooler (4 days and counting) and made the rounds of all three of my boys. Dahl's pretty funny even when writing non-fiction, apparently. (I love the sound of laughter when they're reading... it's not quite as much fun as the giggles they got occasionally from Explode the Code books, but still pretty good.)