Wellington's War: His Peninsular Dispatches (Julian Rathbone, ed., 1984) is composed of selections from Wellington's dispatches and correspondence during the Peninsular War, woven together with commentary and narrative by Rathbone to make it comprehensible for the modern reader, who lacks the context Wellington and his correspondents had for the events described.
It's an informative read if you're reasonably familiar with the war and want a better window into Wellington's mind, but it's an awkward read because Wellington's terse, impatient style clashes with Rathbone's chatty narrative. It wouldn't matter if Rathbone's narrative stood more separate from Wellington's writings, but they're woven together, sometimes within the same sentence. Reading it gave me whiplash. Also, Rathbone has such an obvious man-crush on Wellington that I was almost embarrassed for him--and I share his pro-British, pro-Wellington bias!