I always thought that Cornelius Ryan did a wonderful job compiling the individual stories of soldiers for The Longest Day, and A Bridge Too Far.
Although he didn’t approach history in a traditional way, Ryan was a great historian, as far as I’m concerned. Using a narrative structure to relate history, as Band of Brothers was supposed to be, is acceptable in anyone’s book. Using a ghostwriter to make stuff up for oneself is really tacky—but sells books, if one’s name is already known.