Massie's prodigious knowledge of Russian history serves him well here, but it's his ability to tell a good story that makes this book. He's able to blend healthy doses of diplomatic and military history with the larger-than-life personal tale of a powerful woman who rises to rule one of the largest countries on earth.
The most interesting sections for me were those concerning the bloodless coup that brought Catherine to power, her long-running correspondence with various Enlightenment figures, like Diderot and d'Alembert, and the fascinating samples from her correspondence and memoirs.
Clocking in at almost 600 pages this is, like most of Massie's previous works, not an insubstantial read. But he's paced it well, and I had a difficult time putting it down once I got started. With the minor criticism that the last few chapters felt a bit too rushed, this is by any measure a very well done biography.