This isn't a formal Goodreads review because the book isn't in their database, but I wanted to comment briefly on it. I did read this book somewhat out of order - it would have made more sense to read her biography first - but I had already started it when I realized the nature of the book, so I decided to push on.
This book is an exhaustive analysis of Mercy Otis Warren's writings, how it fits in the framework of the times, and what she was trying to achieve with each type of writing. It covers her exhaustive letters to family, major political figures and female friends, her poetry, her plays and (almost paranthetically) the history book she wrote. Richards' book is dense, with long, complex sentences that sometimes need a moment to sit back and process. And I found it fascinating ... for the history, yes, but also for the thoughtful discussion of literature in context with the time period and purpose.
To some degree, the book is apologetic, framing Warren's weaknesses in context with her unique religious and political perspective and her purposes for writing. However, Richards balances deftly and avoids making his text a statement that we should ignore the flaws in favor of what the author was trying to say. He is honest about where her works make for compelling reading and character creation (esp. the plays, of course) and where they come up short.
I cannot put my finger on a specific writing-related thing I learned from this book, but I found it very absorbing and educational on a front the author really didn't intend. Of course, there are great pieces of history here, as well - the discussions of Warren's letters to the Adamses (Abigail *and* John) and the British author Catherine Macaulay in particular - though it's ultimately a specialty book for a reader interested in literature of the period.